Yep, interesting how that massive cut of revenue doesn’t do a thing to actually help consumers, who as a consequence are shunted with the bill anyway.

Not only but also; as with a real tax from a government, all the money goes into a big pot, gets mixed around, and then the expenses come out unevenly from that pot.

I'm not at all aware of where the boundary is between "that's fine" and "that's abuse of market dominance to fund uneconomical expansion".

Does anywhere have a specific "national defence" tax and another "police fund" tax etc. for each expense, rather than "income tax" and "sales tax" for each source?

IMHO profits should be ringfenced by activity and taxed accordingly - otherwise you end up with funds from one activity being used to subsidize another without taxation, creating an unfair environment for competition. Youtube being the perfect modern example.