I dunno, last phone I’ve held was the iPhone 4 and recently bought the iPhone SE 3. Personally I’d stick with the SE, but mom may like the extra screen from the 12 mini. It really depends if your mom has a visual impairment or not that would determine what phone you’d recommend to her.
Definitely bought 2 myself, I realize that my pixel 7 will forever be my primary phone but it never hurts to have an SE on a tablet plan with my metropcs account and use it with unlimited data and keep the other as a spare for when mom travels.