I recently worked on an app that adopted a similar framework (ReSwift) and I hated it for the same reasons you are skeptical. It was needlessly complex, horrible to try and debug, and was incompatible with the "status-quo" of standard app development practices.

At the end of the day it was just a bad replacement for Core Data / Realm / whatever.

I wish I could tell you more but like yourself I really had absolutely no idea what the point was or what it was supposed to make easier.