I imagine DAWs like many others could be a very small native audio processing binary with a gui on top that can be whatever it wants. Some are already Java UIs over C++ backend (e.g Bitwig). Should be possible to do an electron or web frontend over the C++ backend too. Replacing the processing bits will be hard though. Driver interfaces aren't exactly the strong point of web dev.

Funny that the other day I discovered bandlab. It's not professional but for my hobby usage it's the best I've found

Same here - I was a Cakewalk user back in the 90s, and decided on a whim to find out if it was still around.