No such thing as a decentralized pyramid, friend.
Decentralization is built on flat architecture.
With yield farming there are trading fees coming in to the system, which means the pie grows.
First of all, over the next year CUB will have 1000% inflation and these trading fees you're mentioning are 0.17%.
A total drop in the bucket that means nothing to anyone.
There are dozens of these Defi Protocols that are legit scams.
Employing your logic all these obvious scams are actually not scams.
The logic itself is flawed.
The only way for CUB to not be a scam is if it receives constant development and becomes more sustainable.
Otherwise just stick to Bitcoin.