The project was archived back in April. I assume there were multiple incidents along the way, but the final straw was the discussion in this thread:

https://github.com/nvim-treesitter/nvim-treesitter/discussions/8627#discussioncomment-16440673

Basically it is just people demanding things from open-source developers and behaving like shit while doing so. These guys don't have any respect for the work other people do for free in their spare time.

I use a lot of open-source software, but I usually don't interact with the developers. Whenever something like this happens I feel like we as a community should show our love and appreciation for these projects a lot more, so that devs don't burnout due to this loud minority full of negativity and sometimes just plain harassment.