And the sync is locked behind their offering, if you use other software to handle the sync, you're out of luck if you want the data to be available on mobile since you can't dynamically choose the location of the vault.
It's still miles ahead of other offerings when it comes to having the data be "open", but I found this limitation frustrating.
I've been using Obsidian for months now. I couldn't justify the high sync cost even though the offering is nice. So I hacked a solution with the community plugin "remotely save", syncing to WebDAV. I thought it would be shoddy and after 2 days I would just go with the official solution. But no. Obsidian is a "too good to be true" kind of thing.
Also, the fact that it's just files allows me to shamelessly use Restic to back it up. No "intergrations" or "export workflows" - my data is my own (although it might be snooped by the app), I get to decide what to do with it, how and where to put it.
For me, this is the future. Imagine your data is yours. You get to enjoy all the possible ways of making value out of it, not just in some crippled ways that make other rich people richer.
Last time I checked 3rd party plugin 'Remotely Sync' worked fine on mobile. You just create a new vault with any name you want, install the plugin, fill-in the settings and the sync will copy content of your existing vault there. After that sync will work in both ways. Personally, I use S3 backend and didn't encounter any issues so far.
This is only partially true. Their business model is based on business use, not personal use. They do allow free community based solutions. Like Notion - use it for free for personal stuff. But better UX and you get to take your notes home.
You also have to pay for commercial usage. And may choose to pay for early access to updates.