Good question.
"Cheap Copy" ... That's extreme though. You must be aware of other Question/Answer platform/s that exist on some of the blockchains.
IMHO, Musing wasn't a failed experiment/project. There were two reasons for that project to be ended.
- Delegation was lifted.
- Developer of the project was finding hard to work on the project with that much little monetary output.
I hope, this wouldn't be the case with the developer of Quello (You must know him, tobias-g), otherwise, I completely agree with you, Quello will face the same fate.
Other than that, a Question/Answer platform is well needed on HIVE Blockchain, this will not only give the users more interaction but will bring more traffic to the blockchain.