I would like so suggest you reconsider your priorities - all this anger over something existing is probably bad for your heart.
VimR is very good; I've been using it before it started using Neovim as the core [1].
Before I can take Neovim seriously, I need a Neovim GUI that is exactly what gvim or MacVim provide — not something that adds features I neither want nor need nor can I easily disable.
Granted, it’s been about six months since I’ve used VimR, but I bounce off it every time, because it doesn’t work with the configuration that I have built up trying to match my Vim configuration to the best of my ability.
Having used MacVim for several years and now using Neovim mostly in the terminal but sometimes VimR, I disagree that it's a mess.
I get wanting to have a common gvim ui/ux across platforms, but I think having a Mac-like or Windows-like ui/ux on those platforms mostly trumps that.
Also, the special features of VimR, like the built-in file browser and Markdown preview can easily be disabled. Using the native rendering of macOS and support for ligatures, for example, is certainly a plus IMHO.
Given the choice, I can either:
1. Hate every day of working with the substandard state of neovim GUIs
2. Hate every day of working with neovim remediated by a terminal
3. Switch to Emacs
4. Switch to VS Code
or
5. Keep using MacVim, because it just works
I try each of the various active neovim GUIs every few months. Usually, I end up noping out of each one with just trying to edit a single file. For ones that have stuck for a day or two, I end up noping out of them because they are missing key OS integrations or are sluggish or have made decisions to act more like an IDE (Vimr) that result in a UI that’s less flexible than gvim or MacVim itself.
You say that gvim isn’t a great GUI, but that’s a subjective — and IMO wrong — opinion. It is vim. It doesn’t try to be anything but vim. It doesn’t try to add IDE frippery (because you can implement all of that with vim plugins) or switch to an entirely different plugin system where you can’t use any of your existing configuration (Oni2).
gvim — and MacVim — are great GUIs for being separate non-terminal-bound views on vim. There’s not a single neovim GUI that has reached that level, and most of them get abandoned because, in the end, no one on the neovim ecosystem cares because the core project doesn't care.