I made the switch when windows ME was released, right now I'm using win10 for work because of some software that really doesn't have an alternative in Linux but I do run it on all of my other computers.
Benefits:
customization: If you want a desktop environment there's KDE, Gnome or XFCE, if you want just windows or a tiling window manager there's tons of them too
package managers: update all your software on your own terms while you brew some coffee.
scripting capabilities: you can automate lots of stuff with bash.
scalability: do you have a potato computer, no problem, do you have a nice one, even better.
Edit: I forgot to say that I run Debian on most of my machines.
I run GNU/Linux on all my computers except on the one I use for work because I need to run ETABS and SAP2000, I really wish I had the time and expertise to code my own structural analysis software so I could be free of these.
Honest to god if the instance I'm in puts a link to donate with bitcoin (or other cryptocurrency) at the bottom of the page (like the pirate bay for example) I would donate.
Awesome, I just drew a cuouple of frames for John Wick 4