Linear seems like the kind of app that typically wouldn't need this sort of optimization. I could understand local copy of the DB for indexing, perhaps, but not for normal transactions. This app seems like an example of an app that would typically scale well on the backend - concurrent writes for a single issue would typically be rare, and if sharding is necessary for large customers it should shard quite well.

What about this requires more than a few ms (at most) on the backend, and how does a local copy make that better? It seems like a local copy would create even more inconsistency (and if it doesn't, the backend should be fast too!)