Comment by sodapopcan

Tree-sitter is more performant for sure, and its potential for easier text objects is nice. However, Vim's syntax engine is more than good enough for non-complex highlighting (and many people don't want complex highlighting) and, while I don't have enough tree-sitter knowledge to explain this myself, I've seen examples of Lua versions of Vim plugins where tree-sitter is unable to handle some of the regex-based text objects present in the vimscript version.

As far as really cool uses for tree-sitter go, ast-grep is a fantastic tool. Of course it's a standalone program, so it doesn't need nvim to make use of it.