@kissane I can relate to most of that. I was lucky with the Twitter migration - the tools worked well for me. Anybody complaining because I missed an alt text on an image gets blocked (sorry, not sorry - don't need complainers and most of the time I add it).
Overall, my experience here is similar to Twitter was in the early days, though I have a lot more photos in my feed (following the photography hash tag helped there 😀)