Because you have no vision whatsoever.
Multiple classes use swords, daggers, axes, and maces. Just because one class uses a weapon, doesn’t ONLY make that class the exclusive “owner” of said weapon. Ever Warglaives were originally a Rogue thing until they actually added Demon Hunters.
Turrets? Shamans have used totems that fire things off. An actual turret would be a much-improved version of that with better health and a more robust damage profile. One of the complaints about the totem was how overall weak it was, so they would have to buff it to make it more viable.
Bombs? Yeah, Hunters throw those now too. Ever played a Survival Hunter before? Literally part of the rotation. Several other classes have a “thrown” object in their rotation as well. Rogues have icons for their abilities that are actual “bombs”.
As for Mech Suits… it’s literally been a boss mechanic used against us by both Gnomes and Goblins. There’s no reason it can’t be something adapted for player use as well.
Just because “you can’t see” something, doesn’t mean it isn’t possible.
But you can see this… which is exactly the kind of thing we have been talking about in WoW because THIS is exactly the kind of thing Geblin, Gazlowe, Gallywix, and a host of others have been doing (which has been expanded upon) over the life of WoW.
Tinker is just a name we’ve been using since it was a WC3 unit. It could just as easily be called “Artificer” and do all of the things we’ve been describing.
I’ve already described above how other classes are using similar abilities in a limited fashion. Tinker is already an archetype in the game, used by NPCs. Many of the abilities we are speculating on have been used in some fashion by several other classes.
And yet it’s one of the least played classes. That’s not a reason to eliminate them, and people weren’t really asking to have them added. It made sense to do so as a generic “martial arts” character with an expansion focused on “Eastern themes”. If they didn’t add them but people saw NPCs doing it, then people would likely be asking for it to this day, and other people would be like “That’s silly, I can’t see it, there’s no reason to add it, it doesn’t fit with gameplay, BLAH, BLAH, BLAH”
They could just as easily make Tinker (or Artificer, or Machinist, or whatever make it work in your brain) the focus of the next (or a future) expansion and “fit them in”.
And yet Warhammer is one of the most popular tabletop games on the planet. The game is literally “WoW with technology thrown in”. In fact, Warcraft owes much of its “lore” to Warhammer.
Yet you’re ok with us using time travel and going in and out of a literal Death realm.
Good thing you’re not a game developer. This game would be boring if you wrote it.