I use WSL for work as well and in my opnion it fits Microsoft's classic "embrace, extend, extinguish" paradigm.
WSL basically prevents most from requesting from the IT dept, A full blown Linux desktop/Laptop because they will simply say "you want Linux? here have WSL, it is 100% Linux", Which it is really not, WSL's idiosyncrasies from a true Linux Desktop drives me nuts at times.
Damn here I was hoping I was safe on Opensuse TW with Kernel 6.3.2
Thankfully I should be able to rollback with Opensuse's snapper. This is the key advantage of Opensuse TW in my opinion, The BTRFS filesystem alongside snapper helps maintaining a reliable system while on the bleeding edge.
This is a gross generalization. And I'm not sure where you are picking up those values from as well or their accuracy, for Flask is ~15,000 on uWsgi or Gunicorn? or the default werkzeug dev server? How you deploy matters very much I'm sure you'd understand.
However, Ultimately development teams make do with the skillset they have and saved development time is saved money. Who cares of the toolset, Most programmers forget about the business objectives ultimately. Instagram's backend was originally Django, they managed just fine for a long time. Using C++ is pretty overkill even for a simple API project and potentially a huge waste of developer time, people seem to forget developer time is expensive.