The thread topic itself notes that the question posed in it is stupid, and I have to agree with that. Not because the topic raises the question of whether DF could be developed faster or even better in a commercial environment - that's a legitimate question, although the answer would be "probably not", due to reasons mentioned already in the previous posts. But the question in the thread topic *is* stupid for insinuating that indie games, or DF specifically, isn't being developed "properly". That's pretty offensive towards indie game authors in general imho.
For various reasons, Toady wants to have full control of the project. These reasons include that he doesn't want to compromise his vision of the game, they also include that DF would have a hard time finding commercial funding anyway due to being a niche product (thought adorably great within this niche), but the main reason for it, as stated in numerous interviews, is that the DF donations are his main source of income. The current arrangement (funding through donations) has worked so far, and that's why he's careful about changing it, by building teams, seeking commercial funding, etc. The more control he gives away, the less control he has over the project that currently pays his rent and food. Who wouldn't be careful then?
Devloping a project in this way is not a new idea by any means, it happens every day, though it's still a bit more common in other businesses. There are artists all over the world who *could* get more commercial success, or a better working environment, by giving up control over their work, but who don't want to, for various and very legitimate reasons. That doesn't mean they are not doing their work "properly".