For me it was that it worked mostly just like Kakoune (or at least, the parts i used of Kakoune) with nicely integrated LSP. It also had TreeSitter based movement options and themes, which is really interesting too. A potential future where vim-like navigation is done on TreeSitter objects is attractive.

The potential DSP integration is nice too. And to top it all off, it's made in a language i enjoy and within the first 24h of using it i had a PR made for a small feature i wanted. Being able to contribute in a language i enjoy was nice.

I don't use either one, but just from reading the comments here: using treesitter for syntax highlighting and having LSP configured out of the box (for kakoune I think you need to install an extension called kak-lsp).