> localStorage suffers from issues like size limits and performance

Absolutely, but _it works_ and nothing trumps working code ;). A slow and space-limited database is better than none at all!

We implemented that functionality primarily to make peoples' eyes bug out ;), but also so that folks who don't yet have OPFS can have some form of persistent sqlite databases.

The lack of guarantees about longevity put it in the realm of local cache, not buffering. If I can't count on the data to stick around then its use case is predominantly for consumption of data, not creation. We ought to pay more attention to how often we make systems whose sole purpose is for consumption.