Hardware not working as well. Poor battery life. Worse game compatibility. Worse stability (yeah really). More bugs (yeah really; at this point Windows is quite a bit less buggy than Linux in my experience). More annoying to configure things / set things up usually.

Those are all only on average. Obviously there are times when Windows has bugs or sends you to the command line or fails to connect to WiFi or whatever... But by this point they're pretty rare.

I use Windows and Linux regularly and for Windows my complaints are:

• If I leave my playstation controller plugged in the PC never sleeps. Took me a while to figure that out! Probably a driver bug.
• That's actually it. I can't remember the last time the OS crashed.

For Linux:

• Until I enabled a huge swap file whenever it ran out of physical ram it would hard reboot. This is just Linux's shitty memory management.
• I recently installed a kernel update and now it hard freezes every week or two. I'm guessing a driver bug. Impossible to debug though.
• Sometimes when I unplug the laptop while it's sleeping it gets confused and the only thing it responds to is the power button (it does a clean shutdown but that's still annoying).
• Quite often the login screen freezes for a few seconds when I try to put my password in.
• It asks me every time I plug my headphones in if they are headphones. Take a hint! Windows never asked that.
• I set up a network to auto-connect to a VPN, then deleted that VPN. This confused the absolute bejesus out of it so it wouldn't even connect to WiFi. No error messages. Even dmesg only had some vague deauth message. Took me a long time to figure that out!

There's definitely more that I've forgotten.

In fairness this is Linux running on a shitty Dell laptop vs Windows running on a normal desktop. Still...