Wouldn't carrying an actual shield be easier and be more durable?

I'm sorry, is this some NPC thing I'm too Barbarian to understand?

Probably.

Wizard: I shall also wear armour. Fantasy lore: no, you can't wear that. Wizard: why? I'm going to be fighting too. I don't want to get stabbed by the first guy I see and die. Fantasy lore: no, it wouldn't be fair on the giant dragon or the deamons I'm sending you to fight. Sorry.

Ponder the blue ~~orb~~ balls

Check his pockets, he might have a phylactery.

A fun thing people often forget about Mage Armor is that you can cast it on other people, which is occasionally even helpful!

That's why my oblivion play through is a wizard with a shield and heavy armor.

honestly it's a damn shame battle mages aren't standard, it's such a cool concept Imagine shields specifically designed for use with magic, with a slot cut out on the side for your hand to be exposed so you can cast spells

I mean, I could see it was a screenshot from another social media.