You can add captions to images inside text posts - those are used for alt text. You can’t add alt text to image posts though.
Trust me, I would know.
Incidentally, they’re automatically adding the subreddit and post title together for the image’s alt text, which still doesn’t include OP’s name.
I really enjoy Mini Metro. I’ve been addicted to Dots for years, it’s the very best digital fidget.
I paid for a Need for Speed game some 8 years ago and that was pretty OK for a few hours.
A Dark Room is also really good.
That’s about it, to be honest. If you want to pick up a controller, there’s a decent library of older PC or console games that run on phones now - emulators are also an option.