Larian Studios Forums Baldur's Gate III Baldur's Gate III - General Panel From Hell 3 (LarPG) : summary of announced features

I am definitely in favor of the additional resource management. I expect an option to disable that eventually, but I will bet that for the next patch at least we will all have to use it.

FYI Warlock is a good caster choice if you are less of a fan of the resource management, since you get spells back on a short rest. Monk (when implemented) also regains resources on short rest.