We have a full kit every expansion... until we have to level again. We have Logos, Lost, and Phantom Actions... only while in Eureka/Bozja/OC. And our additions at endgame commonly come with degradations to the leveling experience. So while I can understand the dislike, I have to wonder why this would seem a new issue...
Yes. Which is, honestly, fine. We had an experiemental stage over which to player-test a bunch of different ideas, many of which might be too "out-there" for baseline kits, from which we could then pull into the game not just the ideas the devs thought players would like best but which the players actually did most enjoy according to surveys and other forms of feedback.A huge part of WoW's new talent systems is just about giving people back abilities they stole back when a 'borrowed power' system expired.
To call that "theft", though, seems odd. It'd be like if at level 98 WHM got Bozja's Reraise and we called that a "siphon" as if the Bozja ability were normally available outside of it and the level 98 skill were available in Bozja.
Moreover, if we're talking about zone-specific abilities in this case (rather than per some seasonal or expansion system), they're likely to be thematically insulated -- like a desert zone containing Mirage Dance for DNC, Dusk's Suspire for BRD, Sands-cutter for MCH, Zephyr Kick for MNK, etc. Building such skills always with the assumption that they must be useable and fitting in the context of anywhere and everywhere else is going to limit the creative freedoms of those skills' design.
While it wouldn't necessarily be the most efficient use of resources, that SE's biggest cash cow still "can't afford to make a normal mode" seems... pretty ludicrous, so I have trouble really judging when or to what extent modest additional costs in the interest of greater flavor and world immersion would be a net negative.