Before you even get to the rest of your point...Blizz has to balance their game enough to make swapping even worth the effort of considering for way too many specs. While PvP vs PvE has very different builds for most specs the difference between recommended PvE raiding vs M+ vs questing talent builds is too often one single talent or nothing.
Its saved for future xpac so it can be announced as a major feature
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I mean, Blizzard sort of force a loadout feature to be in the game. With talents, spec, gear, soulbinds and whatnot, the game is getting to the point were a loadout is required. It used to be enough just respeccing and/or swap a talent or two. Its much more than that now in SL.