I don't mind a bit of multiclassing, to be honest, although I agree that splashing in 5 or 6 classes gets exhausting.
5e limits this to some extent by placing level up rewards deeper into the class:
ASI/Feat are awarded every four CLASS levels (not character levels). Multi-attack requires 5 class levels (no BaB stacking for multiple attacks). Higher level spells require you to stick with a class (although spell slots do not).
Pathfinder does this a little bit, but a lot more stuff is front loaded (1 level of monk gives wis/cha to AC + a free feat for the most egregious example).