Magic is not underpowered destruction is.
What magic problem is is the fact that it lacks options and variety compared to what it once had in this series.
We use to have spell creation which gave you a lot of customization to your mages and that allowed even deeper roleplaying value by allowing to create spells and spell combinations that your magic user would use the spells then defined your character, you could set their power level and criss cross effects that would suit your build.
Then we used to have a great variety of spells if we could have out old spells back thay would add even more diversity and options to being a mage.
As is in this game being a mage is one dimensional and you have to use the more powerful spells as things level and rinse and repeat there is nothing new. This feels like an unfinished system it feels like a basic foundation to a magic system.
I think this has got to be the first time I've ever agreed with you on something.

Anyway, I do agree that magic in and of itself isn't reallly underpowered, but destruction is what is a bit lacking. Spells overall, as well as a lack diversity is a real problem...especially if we can't have spell creation back.
Is this a basic foundation for a new magic system? I don't know, but Bethesda sure as hell needs to tweak it some, if we can't have spell creation back, then at the very least we need more spells, and better scaling for our spells.