I know your pain. There can only be so much arguing for why allowing non-Windows PC players joining in would be simple and unharmful. But Bungie keeps saying no. It's funny because my only thought as to why they say no, is dealing with tech issues for a flux of people. But IIRC it was Ubisoft that said when they allowed Linux players into one of their games, problem reports increased by like 2000% even though population is so small, so they decided to never do it again. But another studio revealed their data, showing that almost (if not) all of the issues reported, were also issues on Windows and sometimes even consoles. It's just that Linux users are much more likely to actually report issues.