Nefermandias
Hero
Not allowing feats and multiclass goes a long way preventing those broken builds to arise in your game. It also keeps the things simple so we can focus more on exploration, resource management and clever usage of the environment around the characters.I think the primary thing for me is that like BECMI and 2E, 5E puts trust back in the DM to be able to "handle it." After over a decade of 3.x I actually balked a little. "Where are the task DC charts?!?" But I have realized over time that the broad proficiencies and guideline DCs are a real boon to DMs. It is easy to run on the fly.
I will say that one place it also lines up with 2E that I don't like is how imbalanced it is on the player side. As a player I don't care, but as a DM I cringe when I watch one player make all the optimized choices and another make (relatively speaking) suboptimal choices. I have to challenge them both without being unfair! Ugh.
I also feel like 5e has brought back the "adventure" as the main unit of challenge instead of the per encounter basis we had with 3e and 4e. It's more important to plan ahead and preserve resources than making super optimal moves in your combat turn.