This is very true, but iirc Obsidian has a community plugin that solves this. Just checked and its called Relay and even has offline editing. Not sure how its set up, because I know that Obsidian sync is a paid service.

I’d love to move off of Obsidian to a MD editor that’s completely open source, but I’ve tried them all and nothing tickles my fancy. I just love the plugin community for Obsidian. But that’s why I’m working on Neovim, because the plugin community there is HUGE.

Curious, I checked for Neovim collaboration solutions and found this.