That is still the case.
Every 30 minutes we calculate users that are away for 7 days and send a digest.
What did change were some performance optimizations for sites that go days without new posts at
https://github.com/discourse/discourse/commit/c0293339b87c39bbd2b91f87e2d39179f40c9a9a
This can change the digest frequency, but will affect mostly communities in extremes, of either low new post or lots of users who doesn’t visit the site.