The difference between tax and fees is that with fees you can opt in or out of the service they're for. Taxes are compulsory, in most other interactions the exchange of money is voluntary and can be negotiated by the parties involved.

That is why we should take care thinking about tax changes. You are forcing someone to provide money. It's obvious we have to force people to pay for somethings. But how much should they have to pay for? At 70% I think there has to be a solid discussion about the moral implications not just about the feasibility.