Raises eyebrows We're already having the discussion of what we should do about redis at work, given it's a cache, and the tooling we use allows for other caching tools, we'll likely switch away from redis fairly quickly...
Postgres makes for a pretty decent key value cache in certain situations.
Also, with AGPL-style license Redis will not become less popular. Anyone still will be able to use it as a cache, but not as a free work done by others that you can resell without contributing back.