On Github you can find a Discord-Server link at the bottom where you can ask questions :)

Hey, glad you found BetterDummy. I wanted to switch from windows and was also quite shocked when I compared it with the blurry "normal" display image (see page 5 for an comparison image I took) . I talked a lot with the Apple Care with reference to this thread... at the end I was talking to a senior Apple Care person (support was escalated two times) who told me "that he recommends to send back" the newly bought M1 Pro Max because the issue will probably not be fixed in the next year... This thread here will not change anything. If you are unhappy about the current situation use the feedback tool provided by apple. It is the only active watched metric (according to senior Apple Care)! Apple Feedback

Sadly does not fix the issue. I just tested it and in safe mode the m1 macbook has exactly the same display resolutions. No 3440 x 1440 (HiDPI) possible!

According to the author of BetterDummy (who already has tested the Ventura beta and talked about it on his discord-channel) this is not fixed. I switched back to windows because I do not accept to buy a new display.