I think that's unfair to audio developers. You're asking for a real-time scenario from an obvious not real-time OS. Dropping audio is a lot more obvious than dropping video frames. Audio also deals with /a lot/ of plugins both hardware and software--many paid (years ago and now abandoned). Most people I know with an audio setup are very sensitive to physical changes due to subtle problems.
I also think it's unrealistic for large applications to be 100% ready on day one. It's not like Apple has a GM ready weeks ago. Betas are known to change and nobody really knew when Catalina would ship (many people are surprised they're shipping what they have).
Audio software is very hard to get right and it's a relatively low margin business. Asking them to track new OS releases on day one is just not realistic, especially when Apple has a pretty bad track record on stability and maturity of x.0 releases of macOS.
I also think it's unrealistic for large applications to be 100% ready on day one. It's not like Apple has a GM ready weeks ago. Betas are known to change and nobody really knew when Catalina would ship (many people are surprised they're shipping what they have).