"not having a JIT" is not a problem, it's you speculating that a JIT will improve performance, the real problem is "GDScript has poor performance", which in this context (me saying C# in godot sucks) is you speculating that C#'s performance is better than GDScripts. Do you have any data to back that claim up? Like real world data from a real product? Or are you just speculating with vibes?

If performance is a concern, skip C# and go straight to c++. Now your ripping at max speed with the smallest binary! That's my whole point. GDScript + c++ is my point. Ditch C# it's not worth the squeeze.

Some people like nice tooling with performance.

Interpreter code is never faster than a dynamic compiler, otherwise what about doing games in Python?

As mentioned on my comment, GDextension experience kind of sucks.

Lots of excellent games are written in Python, Lua, JavaScript and GDScript. These abstract criticisms are just that, abstract.

I'm offering real practical advice from experience of having worked on real projects.

I'll make it real clear:

GDScript & c++ > C#