He's just incompetent:
1. He blames the maintainer that his distro doesn't ship latest neovim.
2. He didn't pull neovim from the Extra-Testing Arch branch.
3. He didn't pull neovim from AUR.
4. He doesn't have the knowledge to build from source.
5. He didn't pull the tarball from git.
6. He didn't pull the AppImage from git.
There's so many solutions to choose from and he chose none; pure ragebait.
You should totally post this on the original thread just for adjustment :-)