> Features I find useful have been removed.
Which ones specifically?
> significantly other Vim9Script
What do you like more in Vim9Script?
> Gvim is useful at times.
What are your use cases for the GUI?
If I look at some Lua plugins and compare that to some of my Vim9Script (or even "legacy VimScript") plugins then I think /Vim9?Script/ "wins" hands-down; it's just much more convenient for programming an editor. It also doesn't help that IMHO Lua isn't all that great of a language to start with – it's not horrible either, just not great.
On Windows gvim works loads better (even on Unix systems gvim is arguably better, because terminals kind of suck and you run in to loads of graphical and input limitations pretty quickly).
But in general: neovim doesn't offer me anything I want or need, I will have to spend time on migrating (e.g. my vimrc would error out, I need to deal with changed defaults, etc.), and for most things I prefer the "highly compatible" attitude from Vim/Bram, which is a trade-off that's not without its downsides, but I really like it (for most software).
I don't want to type like it's 1976. I want something simple and easy to use similar Notepad / gedit, but that still powerful when needed.