How I feel about mana depends largely on how quickly it regenerates. It can be just a reskin of spells-per-day or spells-per-encounter, or it could be something more interesting.
DA:O had unlimited mana potions, which meant essentially you spend a small amount of time to refresh mid fight. Not very deep tactically, but more or less fine.
I don't think resource management is really a thing most people actually enjoy. Most people don't like timed missions, so you probably don't want to use that to prevent people from resting a lot. You don't want to soft-lock players by letting them blow their resources too soon, so they can't win the fight but don't have a way to restore. The dark souls style "you reset at the checkpoint but so do the monsters. Keep trying until you get it right" works for me, but a lot of people hate that.
There are so many ways you could do magic, and it's a bummer that vancian magic takes up so much space.
DND just isn't as good and universal as people think it is, but it's hugely influential anyway.
Side note: DND is balanced around like 6 "medium" encounters per day. You're supposed to slowly trickle down your resources. Turns out most groups do one encounter per day on average, and then the system doesn't work very well at all. There's lot of patches (eg: gritty realism) but the problem remains people don't seem to want to do that kind of cadence.
This topic is one of the things that brings up how people are emotional first, and sometimes only.
Like, I'll point out all the problems with golf, and all the better things we could use the space and resources for, and the pro-golf person will respond with "but i like it" as if that means a fucking damn thing.
The fact that some people "like" golf is not enough to justify the poor use and allocation of resources.
(Yes, I realize I'm holding onto a years old argument I had with a peer and that's not especially healthy. But I feel like this argument comes up all the time. I'll be like "We can't keep building for cars-first. It's bad for the environment, bad for the neighborhoods, bad for the economy, bad for the people in the cars" and they'll just go "But I like my car" as if that refutes anything at all)