Activities for someone who is losing their vision?

Wow!!!!! I’ve never heard of this! Amazing! Thank you so much!

Your Mom can get digital books for free from The National Library For The Blind. It's through the Library of Congress. They have digital magazines, digital books, etc and will provide a Digital Tape reader/player for free. Link: https://www.loc.gov/nls/ or call: 1-800-424-8567 for questions about applying.
Even the postage is free when you send the "books" back.

Podcasts! There are so many — they are like radio shows but very specific to certain interests. I'm currently listening to the Office Ladies, where the actresses who played Pam and Angela on The Office rewatch every episode and talk about it. And there are a million more. What does she like? I'm sure you can find a podcast about it.

There are tv sets that can have audio descriptions of the scenes, like captioning for the hard of hearing, but for vision impared people.

She might like listening to radio theatre from the 30’s (just type in ‘radio theatre’ on YouTube and a ton comes up.

Also, maybe she would like to paint? You could start off with watercolors and she could feel around her paper without marking it with her hands (unlike acrylic), of course, she might enjoy finger painting. There are several blind painters out there, and their work is incredible. It doesn’t matter if hers will be, but she can paint from her mind and memory. It’ll probably turn quite abstract, but she might enjoy it.