Network Effect is the biggest hurdle for sure. I think it it true for so many other services too. I think we can agree there is no real technical problem to solve, we only look at the technical problems because trying to “fix” the social and political issues is a lot harder. Digital Markets Act is supposed to address this but time will tell if it has any lasting impact (in the EU).
And they have know about it for a long time… https://climateintegrity.org/plastics-fraud