I hate to break this to you, but Vim itself is in the process of converting its runtime files into Vim9script (which is Vim specific), and many new Vim plugins are also being written in Vim9script.
Neovim has always supported "traditional" Vimscript, and has ported all runtime file changes from Vim (think filetype plugins, syntax highlighting, etc.). In fact, we explicitly request that any runtime file changes first go through Vim precisely because we want to keep the two projects aligned. But the more that Vim transitions to Vim9script, the less can be shared between the two projects. So unfortunately the "fracturing of the ecosystem" is not specific to Neovim.
From my perspective as a vim user, neovim has only made my life worse by splitting plugin authors into two camps without any real benefit over what we had in vim. The only good thing about neovim is it caused some nice features to be added to vim, which the neovim authors could have just contributed themselves without trying to fight for control of the ecosystem with Bram. Neovim has really just made things worse for everyone.
Vim ecosystem is 'controlled' by the community not Bram. If Neovim/Lua is not good enough there wouldn't be a fracture in the first place.
The fact that Bram saw the success of Lua with Neovim but insisted on inventing Vim9Script speaks for itself. Yet you somehow manage to blame everything on Neovim.
I see what you did there.
It's his project he can do whatever he wants, but I'm planning on using this tool for the rest of my career so I went with the fork. Moving my config to XDG_CONFIG_HOME was a welcome side-effect.