Elizabeth Warren has even called to dismantle several of these companies. Few politicians go quite as far as Warren, but most of the Democrats running for president in 2020 have called for more stringent regulation of technology companies and several Republicans including Ted Cruz and Josh Hawley are even making noises about it.
The most of it was initially caused by the Facebook scandals that in turn amplify any tech story, from Amazon Basic competition tactics to Spotify arguing with Apple. Still, nobody produced a viable plan for regulation or breakup of those companies. I don’t think any of those options would work, as we’ve already seen that large-scale regulations on tech either make incumbents straight-up illegal (like the new EU copyright law) or entrench their position as new startups won’t be able to spend $100M on Contend ID system. And if you want to “break ‘em up” you should realized how different they are.
Facebook is a pretty narrowly focused company, running three big online services (Instagram, WhatsApp, and Facebook itself) that might superficially look like competitors. Apple is a behemoth of vertical integration, producing hardware, software, and online services that mostly work as an integrated whole. But Google, Amazon, and Microsoft have all become pretty classic conglomerates, with a sprawling array of loosely related businesses under one roof.