Things are slowly starting to get better in a lot of the fields I interface with.

Payroll and accounting software? Many great browser-based offerings. Unfortunately that also means the backend is running in the developer's servers, but these applications were generally proprietary to begin with.

EMR company I've done a lot of work with (used to be an engineer there), has essentially halted progress on their Windows-only native client (and it was DEEPLY entrenched in Windows) and is now browser based, retaining 99% of functionality. This one always connected to a proprietary backend anyway.

Own a VW, Audi, Seat, Škoda, Bentley or Lamborghini (depending on model year for some of those)? The popular 3rd party diagnostic software for those, called VCDS, now has a mobile variant if you buy the wireless dongle instead of the cable - it runs a server in the dongle itself that you connect to via wifi, and it displays the sofware as a website. Of course it's available for non-mobile browsers too.

Common theme among all of these is that none need to do heavy data processing on the client - though nowadays that is also solvable using WASM.

I mean, at my work we mostly have operating apps that just run inside browser anyway. Our mail clients also run in browser. Only some internal apps are something specially that feels like JAVA designed or something that should run on Linux as well. We could easily use some Linux distro and with KDE or Cinnamon/MATE/XFCE it would be roughly similar to Windows 11. Most people have no clue what version we have, they just know it's Windows. You could just tell them it's special new version of Windows for companies and they'd just eventually adapt to it not knowing it's not really Windows at all.