I'm glad to see that Vim9 continues to make progress. The center of gravity may have shifted somewhat towards Neovim, but the Neovim ecosystem currently seems targeted towards people who want something more IDE-like.
One question is: will more plugin authors move to Vim9Script? It seems that Neovim users have generally moved towards Lua-based plugins, so there's less of a motivation to produce plugins that support both Neovim and Vim9.
I'm not the target for your question (I distribute 0 plugins).
But Lua support in Neovim is the primary reason I moved over from Emacs. Elisp and Vim are both so heart sink for me.
That said I'd have preferred something other than Lua if I had the choice.
I love vim9script and write most of my plugins in it now unless I want something to work in the other vim as well, of course. Really happy to see it evolving and I'm particularly happy that tuple support has landed!