Yes, this is might constant nightmare too! Around 10k photo files Android starts to be painful to use. like app file browser taking huge to show the file list or crashing, and as you said, terrible experience when trying to get files on a computer.

This is mostly because of the mtp protocol that is really shitty, supporting only a single channel at a time and having to send the whole list of all files in one time. But also because Android implementation of it is very buggy.

I was always stunned that for a dozen years, Google stupidly spend millions in reworking uselessly the UX twenty times but never solved real pmserious usability problems like this one!