Sorry, may not be the solution you asked for, because it is for NSDataAssets, not Data itself.

Sorry, perhaps I misunderstood your code, but the old Observable API is known for not updating if model classes are nested. The new Observation API is better to detect changes in classes nested more than one level deep.

There is some kind of backport https://www.pointfree.co/blog/posts/129-perception-a-back-port-of-observable of the Observation API to earlier system versions by some very awesome guys. Perhaps look into that.

There was no announcement of a new version this year. If I'm mistaken, please send me a link, where anything about a new version was said.