Well done on your viral tweet that got some personal attention from Apple. Usually when I spend days narrowing down Safari bugs to minimal reproducible test cases, finding workarounds, and writing everything up in detail on the webkit bug tracker the only public response from Apple is the radar importer bot, and then everything goes quiet.
Btw, your original twitter thread implies you were the author of the bug report. Minor annoyance, but I did spend quite a while writing that up :)