MoP is widely loved because of its quality. Very few actually felt happy to see the expansion dominated by Kung Fu Pandas and a class devoted to them.
Let me tell you this. The game is openning up an arc which is about Light vs Void. The Void is currently extremely underpresented through Shadow Priest. Now, we see Sylvanas is getting Xalatath along with the possibility of integrating the Void to her Dark Ranger arsenal just like Alleria.
With that being said, we finally get the possibility of a Void-based class and you are calling it a joke because you are parroting internet memes about "edgy" and other autistic nonsense? As for your suggestion, you consider a class that comes straight out of children cartoons, screams filler and has a mundane/irrelevant theme to be a better option to Dark Ranger because you think "internet calls it edgy, so it it has to be comical!".
The same community that asks for "war in WARcraft" and "gnomes are there to be punted", now asks for a class that is the Gnome silliness incarnate. I don't know who or what is more of a joke here.
Irrelevant theme? There's a lot of technology in Warcraft: Gnomish, Dwarven, Goblin, Draenei, Belf, Nightborne... And you just throw it all in the garbage as being "filler" and "a joke". Where's the technological representation in playable classes? Only Hunters have some bombs and mech pets, but their theme is ultimately about nature. Void and other shadow like stuff have representation in Priests and Warlocks and even Sub Rogues, and a whole race that makes classes like Warrior look shadowy (VE).
We don't have any class about mechs, electrical machinery, big focus on bombs, etc. A tinker would be far more refreshing that another "dark magic" class, specially if its only dark magic MM hunter class.
Tinker/mech classes won't happen.
Look at the new classes added, since vanilla:
Wrath - Death Knights. Arthas related, created to counter Arthas
Pandaria - monks - created to counter the Sha's
Legion - Demon Hunters - created to counter the Legion
Tinkering/mechs are a profession in WoW, not a class. Classes are created thematically, to match the expansion theme. There's no way they'd make an entire expansion around gnome/goblins. They'd lose the majority of subs.
The way it looks, they're heading towards an Old Gods expansion, and that means, if they make a new class, then it will be one that counters the Old Gods, so that would be most likely Titan themed. Or void based, because the Old Gods are from the void, and what's better to attack an enemy, than someone or something from the same place. Like Alleria and her new mentor she met in Argus?
PS - Warlocks are not void based. They're fel based, there's a massive difference.
Underground titan expansion incoming, with Gnomes and mechagnomes becoming tinkers (and goblins).
Engineering doesn't offer the tinker class fantasy, it only provides mounts, toys and some weird enchants. A tinker could be a medic, a mech tank, or, for example, a canon/gun user with combat turrets, electricity, and so on.
And Warlocks use shadow magic as well, and they summon void lords. Literaly Void Lords.