Even though way more machines work great out of the box it's pretty clear your machine isn't one of them. Unfortunately since manufacturers often don't care about linux support on a particular box buying a machine and hoping its supported isn't an optimal strategy on linux or mac.

There is nothing about linux that would imply screen lag or keystrokes its pretty clear that something was clearly broken with your gpu driver. For example using software rendering rather than your gpu. Possibly something that could have been corrected by using drivers that aren't "horribly outdated" which are certainly available.

You didn't happen to think all the people using linux are just dealing with keysstrokes that take seconds to show up and pretending its normal did you?