I am partial to your sentiment but I don't think writing all the terminal handling code in elisp gives us code that might be too interesting to read (to me at least).

Understanding the VT state machine and all its quirks and inconsistencies is not high up in my list of code I'd like to learn. It is good it is packaged up in a library and emacs is just a consumer of it.

libghostty will have excellent compatibility and features rather than an elisp implementation that maybe half baked.

I stopped living in the world of turtles all the way down. Now I'm more like, hey is this is good library ? Is it integrated well ? It does not matter if it is in zig, rust, c++, lisp, scheme, ...