I got an email from Qobuz support today. A real person, not a bot.
The company is aware of the issue with QC and will address it coming updates.
As noted, it is fairly complicated as QC must be addressed and shown to work reliably on each streamer/DAC.
As misstl noted, an advantage to QC connect is that you can use it with endpoints anywhere. Roon ARC is supposed to do this, but I have not been able to get it to work reliably.
Qobuz limits streaming to AC, while Roon allows multiple sources and saved music. It is difficult for one service to provide eveything one might want.
That being said, Qobuz is a good company, best there is for streaming classical music. I look forward to it being more reliable.