I want someone to come in and crush entrenched rent-seekers by building and scaling better, cheaper products. There are only a handful of companies in recent memory that have managed to do that - Walmart, Vanguard, Uber/Lyft, and arguably Airbnb and Robinhood are the first few that come to mind - and I can't think of any other than Amazon that have done it in multiple spaces (CPG + IaaS so far).

I'd prefer if different startups did it in each of those industries, but I can live with Amazon taking over the world if it means that health care no longer sucks and selling a home no longer costs 6% and kids in underfunded school districts get their questions answered.