In theory it shouldn't matter.

In practice, with the current subsystems, it's hard enough to composit (?) windows, let alone unredirect fullscreen windows. For example, there's a tunable in KDE to "unredirect fullscreen windows". Guess how well it works?

https://bugs.kde.org/buglist.cgi?longdesc=unredirect&lon...

It does! Tried running minecraft on my old Pentium 4 laptop under Ubuntu in fullscreen.

With compiz ~8fps , without compiz ~25fps