It's pretty difficult to acknowledge a supposed flaw pointed by a guy who knows a guy who uses Linux when you have never had it yourself.

I used Linux at work for years. Sleep just works, external monitor also just works. HiDPI was rough at the start but works fine now.

Touchpads do kind of suck. I generally really dislike the default mouse acceleration. Font rendering is still so so if you don't have a HiDPI screen and the most popular desktop environments are still kind of terrible.

But sleep definitely does work.