Of course it only applies to some builds, like anything else. A couple extra bonuses to avoid negatives on savings throws can be nice though, if the goal is to reduce weaknesses.

Honestly, every class should get at least one skill with expertise. Maybe pick one from their class list, like a Fighter with expertise in Athletics so a Bard isn't better than them at throwing goblins around. A Bard and Rogue would just have more.