Lurking in forums, I’ve seen this comparison popping out quite frequently.
Thing is, I’m pretty sure Blueprints are copyrighted; this guy have read through UE4’s source code, learned from it then replicated the system to sell it to Unity users.
This could be classified as derivative work and potentially copyright infringement…
I am surprised Epic Games did nothing about this specially because Blueprints are the singularity in the UE4 echosystem and somebody out there is blatantly cloning system design, making bank out of it.