Another pain is when there's no long options to use and you want to leave comments to document the short options, bash doesn't have inline comments and multiline commands break if you try to comment a line. There's awkward and verbose workarounds like https://stackoverflow.com/questions/9522631/how-to-put-a-lin... but open to tips!

I'd argue that short options aren't particularly more likely to be portable. Years ago I was debugging a CI issue that turned out to be caused by a script hard-coding the short option for base64 decoding, which was not compatible across the GNU and BSD versions (one of them used -d and the other used -D, I can't remember which was which, and that's basically the same issue honestly). I was trying to figure out if I needed to check MacOS versus Linux (I think I was fixing the newly-added MacOS job at the time) when I realized that they both used --decode as the long option, which meant that the long option being used originally would have prevented the issue in the first place.