> I am surprised in that case, since I experience Emacs GUI window as a
> much better terminal, but might be just me :-).
I have heard (and found) that TUI emacs can perform better than TRAMP
(at least at the moment) over an SSH connection. Perhaps this has
something to do with it?
With the intake of Vim users, there could also just be a number of
now-Emacsers who are familiar with working in a terminal.
The TUI interface can also be more consisent across platforms. Also, depending on the setup, running emacs from a terminal can result in a TUI version rather than the GUI version and given on some systems (like macOS), starting Emacs from the dock has some added complexities for environment settings (because apps run from the dock don't run inside your login shell). Running inside the terminal as a TUI instance tends to isolate platform differences a little - for example, depending on which version of Emacs you are running on macOS (macports, brew from source, etc), the fullscreen/maximise functionality tends to vary when running as a GUI. Running in the terminal as a TUI makes things a little more consistent and if you do also run remote, everything is consistent.
Plus I've seen quite a few people who also like to use tmux. For example, this is one setup I've seen for pair programming.
All of this means a TUI instance can make everything feel more consistent when working locally and remotely and when working on different platforms.
Your point on tramp is also valid. I love tramp and use it a lot (I also use GUI rather than TUI), but in some instances, tramp can be less reliable or slower than running Emacs remotely. The downside with running remotely is maintaining your emacs config, but having it in git can simplify that somewhat.