It'd be extremely easy to limit the impact of it by not eliminating the freebie for everyone, recognizing that there's societal value in enabling these online marketplaces.
Think Systematically Important Financial Institutions [1]. The "too big to fail" banks bear the toughest capital requirements, your local community bank doesn't. The same can be done for the tech industry.
[1] https://en.wikipedia.org/wiki/Systemically_important_financi...