I wouldn't know if 'most of them' don't work, but I know for a fact that I have one (made by Vivanco, using a Prolific chip) that works fine in combination with

I wouldn't know if 'most of them' don't work, but I know for a fact that I have one (made by Vivanco, using a Prolific chip) that works fine in combination with my IBM 5160. I use it in combination with FastLynx, which still works even under Windows 11. It's the only one I've tried, so I've not encountered any that didn't work.