There are plugins allowing you to sync via other means (for free). I don't know how the author fails to realise/mention this. I've been using Remotely Save with WebDAV or years without issue.

And the notes are all just markdown files. If the obsidian software were to disappear you have all your notes. It's fine someone wanted to spend a load of time writing their own software but none of the reasons presented in this piece make sense.