I don't think that will solve the problem. Even if the ISP can't tell where most of your traffic is going after it leaves their network, they're still going to

I don't think that will solve the problem. Even if the ISP can't tell where most of your traffic is going after it leaves their network, they're still going to be able to be able to differentiate between that traffic and traffic destined for a service they control or a third party service that cooperates with them. It stops them from penalising a particular third party service, but not from penalising everything they don't recognise in favour of what they do.