Obsidian + Git already does this. The conflict problem is real though, CRDTs would be better but then you're rebuilding the sync layer anyway, which is what the paid services give you.
CRDTs are technically interesting, but I don't know how they solve fundamental merge issues? If a line of text is updated on two independent paths - there is no automatically correct merge decision. Is it just that CRDTs provides systematic merges for automatically resolvable cases?
For that matter, I guess I don't use Obsidian sync, so how does Obsidian present merges that may need manual input?
For that matter, I guess I don't use Obsidian sync, so how does Obsidian present merges that may need manual input?