I personally think this makes sense. The weights of the network can then be updated through a smart contract call itself.
However, even though the weights might be completely in the open, the fact that you as the owner of the contract is the only one allowed to train the network and upload the weights, means that the people interacting with this contract will need to trust your good intentions.
In the case of the decentralized Uber - the driver and the passenger will need to trust you as a company to train a balanced model. It’s hard for both those groups to say if that algorithm is fair or not.
Another point is that neural nets can have millions of parameters. Updating such a network often would be very costly.
I do think doing this just for the purpose of doing it has merit though.