Unfortunately, optimal strategies emerge because some players are powergamers and some of those like to share their tricks with everyone else, and everyone wants to reduce grind by using those tricks.
If your skill was a base + bonues from gear etc. it would be easier to read, yes. But you would still end up with a surcoat that raises mining or whatever, and all the miners would be walking around in the surcoat.
Alternatives include:
Not giving stat modifiers for anything that other players can see (like clothes) but add it for items they can't see (like rings, spells, etc.)
Having multiple stats that apply to different tasks - for example if you encounter a Goblin you want the weapon that will do the most damage in one hit, to kill it immediately. If you encounter a swarm of rats you want a weapon that does just enough damage to kill a rat but swings as fast as possible. Against a heavy-armor opponent you want a weapon that pierces armor because it has higher overall DPS despite it being relatively low DPS against unarmored opponents. Against flying creatures or those with high movement you might prefer weapons that force them to stop moving (bolas, net, freeze ray) or missile weapons which otherwise do lower DPS but are the easier option when the opponent keeps away from you.
Having huge varieties of equipment, possibly randomized, so that people are looking out for an item with the Bone Saw enchantment rather than a specific Jewel of the Bone Saw which only drops from one boss in one dungeon in the whole world.
A combination of these three, and possibly other ideas that I can't think of off the top of my head, would result in a game where characters could wear just about anything and be optimally effective in whatever job, but still allow people to explore and acquire cool equipment which helps them.