The 30% platform tax is a fantastic example. A giant will always win, or be able to stall a fast-growing company, if they can tax 30% of the revenue and build a competitor without this headwind. Even allowing apps that require people to sign up outside the app, that is a significant growth and conversion hurdle.
Advertising-based apps are untaxed and hence incentivised. However, Google and Facebook have acquired and monopolised the market so that you really can't make good money unless you go through them -- and they get to take a 40% clip. Thus, FAAMG will always grow faster than you because collectively enforce a tax on anyone who might be able to challenge them.
FAAMG is the modern day OPEC, just relying on subtly and game theory instead of outright cartel meetings.
If you want a bunch of super convenient features like elastic compute, you will, but they didn't have those features when they built their flagship products.
Once the entire customer base is locked in more or less, the cartel effect will kick in.