Call a spade a spade. Not even the mafia extorted businesses for 30%. I'd argue an act of digital eminent domain is in order. Imagine being a store owner and having to give a 30% kickback to your landlord.
What do you call Steam, Xbox, Nintendo, Best Buy, Game Stop, Playstation, Microsoft...
If Apple, Google et al want to have control over their digital domains honestly instead of breaking them up let's just socialise the economic rents, or cap it at 2% or whatever.