I'm not looking for embedded, we're talking about a Redis substitute. etcd/consul feel oriented towards running as a cluster and I'd expect overhead for that. FoundationDB is potentially a good shout, but it's not that established, e.g. it doesn't seem to be available in a managed way in cloud hosting environments.

KV Stores seem to be in a kind of split place, existing either as embedded, or full cluster mode. There isn’t really a “sqlite” or “postgres” of persistent KV stores. Cloud providers ship their own proprietary KV-stores: Dynamo in AWS, Bigtable in GCP. If you are ok with hosted, Scylla is also an option.

I’m always shocked that people use Redis for anything other than an ephemeral cache.

Your second paragraph follows from your first - people use Redis in this space because it's the closest thing there is to an "sqlite" or "postgres" for KV. Which is why I think Redis with persistence actually makes a lot of sense and fills a gap in the market.