Few company can amass such quantities of knowledge and leverage it all for their own, very-private profits. This is unprecedented centralization of power, for a very select few. Do we actually want that? If not, why not block this until we're sure this a net positive for most people?
Or, just to follow it through, let's say "WidgetBoss LLC" makes a new Widget that every single human has to have, they become the biggest company ever by making one widget. What will you do to make them smaller? Why?
I have a big problem with Google & Meta, and I can understand arguments about those companies. But not just "big companies" as a generality.
But that's how everyone speaks now. "Literally every billionaire is evil and exploiting blah blah blah"