Laconic: If gameplay was as important as you say, then most people would be playing DF, roguelikes, text MMOs, but no, they refuse to play these games on account that they have no graphics. Their loss.
You know, there might be OTHER reasons people don't play text-based MMOs or MUDs or other games besides a lack of graphics.
Maybe they have no graphics,
and their gameplay is boring and repetitive, too.
I know that the way that many of the MUDs I used to play on were played was to have players make an account, powergrind to the level cap, and then make a new account to powergrind, because there wasn't much to do besides level grind in between brief RP sessions, which rarely had much to do with how powerful your character was, anyway. (And combat mainly consists of spamming the same attacks over and over, at that...)
Yes, game makers today can't be bothered to make engaging and approachable games that are difficult anymore because they are scared of frightening away a larger market share, and put graphics ahead of most else, but frankly, graphics aren't to blame for that. The fact that they make games easy is a deliberate choice made about market demographics, and shooting for the lowest common denominator to reap the greatest common profit.
You want to know why easy games sell better (regardless of graphics)? Then
watch this clip. DF and NetHack aren't just "ugly", they're frustratingly difficult to learn, and filled with YASD to the gills.
Likewise, DF and NetHack aren't as complicated as you'd like to think they are. There's a difference between complex and hard to learn. True complexity is almost never achieved in a game, and some of the games that best achieve complexity are some of the most apparently simple games - like Goh or Chess - while being hard to learn doesn't indicate complexity, it just indicates that the designers didn't bother to explain anything. Hell, DF's help file for the longest time pretty much just said "Losing Is Fun." That's not a tagline for the game - that's Toady's placeholder for a real manual or tutorial. He's just saying to experiment until you DO learn the rules, not that you should enjoy losing.
You can tell that many people aren't really that keen on complexity, because you see people arguing
against complexity every time someone proposes adding it in the suggestions forum. Typically, they're many of the same people who brag about how elite a player they are for playing DF, since it's so complex.
Why do people oppose, say,
Improved Farming? It's too complex. We don't need realistic farming systems, we just need to keep throwing seeds at mud, and make less plants grow because of it.
The same can be said of making dwarves more autonomous, having more complex desires, and being less generally obedient. Having more complex social interactions, and making solving the tasks you need to solve more puzzle-like, and less a matter of direct commands over a workshop whose entire construction of counters, chairs, and tools consists of a single stone.
They're proud of their learning DF in spite of an obtuse interface, but terrified of the actually rather simple mechanics behind the obtuse interface actually becoming complex enough that you can't solve every problem with a binary knee-jerk response.
And while we're on the topic of why you loved old-fashioned quarter-grabbers,
I might as well point out the Skinner Box, the psychological engine that drives slot machines, as well. Getting past level 20 in Pac Man, or getting the 25-kill killstreak reward is just as much a conditioned reward as the rare triple-bars.
If you put DF on the Havok engine, and somehow managed to find a computer capable of running that monstrosity, it would still have all the depth and complexity of DF, regardless of how you saw it.
In fact, the greatest single HANDICAP of DF right now is interface, no matter how much you might want to deny it.
No, I don't mean we need pretty pictures, but what we need is access to the data we need to play the game.
There were many bug complaints about doctors refusing to treat their patients. Mysteriously, doctors just don't treat them occasionally, and ignore patients until they die. The cause was that they didn't like helping people, and so they didn't. But a great many players never even noticed that the doctors didn't like helping people - it's buried in the details page of the 50th dwarf to migrate into their fortress, and this critical piece of information was never checked, because it was drowned out by all the other data that a DF player naturally has to ignore to ever get anything done.
As the game of DF actually BECOMES complex, instead of just LOOKING complex to an outside observer, that means that we need to have real data management tools to be able to understand what is going on in the world we see.
Right now, all we can really see on the map is where the walls are, where the dwarves and other creatures are, the jobs of the dwarves, and maybe some flashing status indicators that only tell us about immediate physical peril or needs.
If we are going to have a game where the complex personality of a dwarf is actually going to matter, as Toady is gearing up to do, we need to see some sort of feedback to actually see that the dwarf HAS a personality, much less what his mood is right now. We can't constantly check the details page of every single dwarf in the fortress every two seconds to try to figure out
We need a visual clue, some sort of flashing sign, that tells us, "This dwarf is happy because strawberry wine is his favorite, but still feels existential angst over the recent death of that dragon that people worshiped as a deity, and the implications for his own religion that gods can die. Worse his son died a few weeks ago, and just plain eating in a fancy dining room isn't enough to counteract that in this version anymore. So he's taking a break right now because you don't have enough religious or psychological support facilities, not because he's just lazy."
You're probably not going to convey all that information with just a flashing down blue arrow. You're not going to meaningfully convey that information to the player by burying it in the back of a detail view that players rarely ever look at.
Until the game is capable of supporting conveying visual information ABOUT the subject that the game is calculating, all that complexity is meaningless; Look at the temperature system, which many people simply turn off as a waste of processor power. Toady just completely reworked it to run significantly faster. Thing is, most players can't see how it really works, anyway. Turning it off just means things don't melt in magma, anymore. No big deal. All that complexity is wasted unless the player can see and interact with the system in some meaningful way.
We already have a bulk of players refusing to play the game without tools like Dwarf Therapist, just because it manages the data that the game isn't capable of sorting for us. That's only going to get worse the longer that Toady puts off the very real problem of his unwillingness to convey the information that is conveyed in his game to the player in a meaningful way.
And that's something FAR more important than "just some pretty pictures".