If anything, big tech is under earning. Google is spending billions on venture-capital-type investments and reinvesting a lot into Youtube growth, Facebook is not really monetizing Messenger, Whatsapp, and is just getting started monetizing Instagram, and ARPUs outside North America are still pretty low, Amazon is reinvesting everything into growth, same with Netflix... Pretty much any of these companies could by choice make its earnings balloon up if they wanted to, but that might not be the best long-term decision for value creation.
Regulatory intervention is always tricky. Can have an impact, or can entrench you further by making it impossible for new entrants to compete because the regulation just makes it harder to operate in the industry for sub-scale players. ¯\_(ツ)_/¯