Can a dominant internet company (Facebook for example, since most people here seem to think they are more vulnerable than the others) prevent its ultimate demise simply by buying competitors and building a Berkshire-Hathaway-style holding company?

If not, what are the confounding factors? Antitrust? Company culture? Lack of vision?

Is big business necessarily the future of tech?

[0] https://www.bloomberg.com/view/articles/2017-02-17/mark-zuckerberg-s-manifesto-for-facebook-offers-a-social-dystopia