Need to save media from obsolete iPad Air

I have an obsolete 32GB iPad Air model A1474. It runs on iOS no higher than 12.5.7 The Home button no longer works, but I've figured a way around that using Assistive Touch, so that's not a critical issue for now.

This iPad stores about 21GB of pictures and videos that I'd like to preserve, but I cannot afford to expand my iCloud storage to back them up (no media is saved in the 5GB free iCloud storage either).

To my pleasant surprise, I recently discovered that the device supports an older version of Google Drive app and I can perhaps (gradually) upload these pictures and videos from time-to-time. Despite this relieving fact, it may take me as well a year or more to successfully upload all 12,000+ media to the GDrive. During this process I can only pray to the tech gods that the iPad remains operational and doesn't die on me or the files do not get corrupted or deleted. I suppose it's worth mentioning here that I can upload only a select few pics/vids at once otherwise the iPad shuts off abruptly.

Still, does the reddit community have any better suggestions on how should I safely go about preserving memorable digital media without having to sell my organs only to be able to AirDrop them to another device?

Also, I'm curious as to how other obsolete iPad owners use their device, and for what purpose? (If they use them at all)