Before blockchain was a thing much less a hyped one cloud computing used it and before that some databases practiced 'tombstones' for databases. The easiest way to maintain absolute consistency has been known to be not really deleting things but marking them as 'deleted' and leaving them to be ignored by default until consistency can be achieved. That was the approach when cloud computing dawned to make things scaleable and avoid the bottlenecks and load-balancing server overhead.
Transaction based databases are logically equivalent to an append only database. If you have a list of transactions that add up to the same resulting database state - with the option of more versatility if you don't constrain things to be operational order insensitive.