On linux mint, zoom works fine, with bluetooth headphones, attached speakers, bluetooth speakers, etc. Has for years (well, I started using it (bluetooth headsets with linux) in 2008 or so, and it worked then as well).
On windows, brand new Dell laptop for work, with an insanely locked down version of windows 10, zoom often crashes, especially when sharing my screen. This in turn takes down many other applications. Generally making the whole windows experience far from optimal.
My Sager Laptop a few years ago, and now my HP Omni (personal) laptop, I regularly drive 2 screens and the laptop display. Works. Out of the box. Work windows 10 laptop, its a crap shoot at best. And I can't use the NVidia card very much in windows 10, simply because the system is so locked down. Thus I'm stuck with an expensive and useless feature. One that works flawlessly in my locked down linux box.
On different scalings for different monitors, its built in to mint.
I'm guessing you are either running a very old version of Ubuntu (literally all the complaints you made are many years out of date, having been solved long ago), or you copy-pastaed from somewhere else. My priors on this are 60% the latter 40% the former.
On my linux laptop, I run windows the way it should be run (if you really need to run it). In a kvm instance. Never touching real hardware. And whats funny about this, is that the virtualized Win10 is faster than the far more expensive windows 10 work laptop right next to it.
Go figure.
FWIW, I've been using Linux on my desktop for 23 years, and as my primary OS on my desktop/laptop for 20 of those years. So ... YMMV.