Not that I'm saying NodeJS backend with Website/Electron frontend is bad, but ASP.NET backend with WPF frontend seems great as well, just with more enterprise-oriented trade-offs, support cycles longer than one year but no cross-platform support (yes, ASP.NET core is a thing now, but that's a very recent development).
And compared to the cost of engineers I don't think many companies are that worried about spending 50% more on infrastructure.
Well, it certainly "runs" on Linux, but there are many limitations and bugs.
And this is typical when porting a flagship application to its non-original OS. I've seen similar issues with Oracle on Windows.