All my games work with Steam/Proton (thanks Value!) and I mainly use my desktop as a gaming PC. I do some bussiness stuff but LibreOffice will work. Or I also use Google Docs to do things--can be saved as Microsoft Office file types or PDF.
But you are right, if you need a Windows only program, then Windows is the only option. I had to update the firmware on my Xbox controller that I use with Steam to play my games. I had to wipe one of my laptops and put a copy of Windows on there to get this done. Another time there was a free Baldurs Gate game from Amazon games I could get, BUT you needed the Amazon Game app to get it. And it only ran on Windows. I put Windows on a laptop, download the free game, then moved it to my Linux Gaming PC. After adding it to Steam as a non Steam game, I was exploring dugeons with elves and dwarves.
It's still a Windows world, but IF enough gamers switch to Linux that could change. And Microsoft is only going to get worse with ads.