If there's no "slippery slope", then why do 3-4 companies control the entire internet today, when a decade or more ago there were 15-20 players? Go even further

If there's no "slippery slope", then why do 3-4 companies control the entire internet today, when a decade or more ago there were 15-20 players? Go even further back and you had a myriad of choices; now Amazon, Facebook and Google have sucked up and shut down just about all competitors. If you don't care, then you don't care. But saying there's no slippery slope? It's capitalism. It's happened with internet providers, it's happened with search engines, it's happened with social media, online stores, it's been funneling into a handful of companies for over a decade now. People want things for free and companies are willing to sell your data to finance their payroll. Saying it won't happen anymore is just naive.