There where two major features shipped with Vim 8, which, as taken from the article:
- Official support for packages
- Asynchronous APIs for packages
Neovim does have those, and has for some time. However, things that Neovim has that Vim does not have, and probably will not have for some time:
- Neovim doesn't require plugins to be written in Vimscript, they may instead be written in Lua
- Neovim exposes pretty much all it's API via MessagePack, so you can remotely control Neovim in an entirely language agnostic way
- A built in terminal emulator, letting you stay within Vim even when you need to do some shell business
- A host of other quality of life improvements that make Neovim a more consistent, quick, and better organized software[0]
[0] - https://github.com/neovim/neovim#whats-been-done-so-far
On top of that, he only started to introduce these features AFTER neovim came and put the pressure on by doing it better... if neovim's approach wasn't better, why would he be implementing features he's previous said he wouldn't implement?