I certainly haven't used it that much, but I never felt like the connection quality was a huge concern for a usable DE. It's something like 30 years old now isn't it?
The thing with X11Forwarding is, it's never designed to be ran over WAN or, slower connections to be precise. It carries X11 commands, not the video itself and is synchronous and doesn't compress anything. As a result it both needs low latency and saturates connections quickly.
When the updates are occasional, fine, but when you call make or run something which updates fast/creates a lot of output, things get hairy, quick. Even on local networks with a couple of connections. Been there, tried that, experienced it all.
X2Go transmits the image, compresses it, and can work with much slower and higher latency network connections. It can also resume sessions.
