They were in the middle of a big upgrade switchover that caused some drama:

https://github.com/nvim-treesitter/nvim-treesitter/discussio...

Really sad. I have been a happy nvim-treesitter user for years.

But the maintainer's reaction is understandable. If you happen to read this: thanks so much for the time and work you have put into the project! There are people who really appreciate it.