Comcast and friends are essentially utility companies. If the internet is "a bunch of tubes", they keep the tubes clear. They don't get involved at the content layer. Comcast may be a crappy provider in many ways, but they've never made the news for politically-motivated network traffic filtering.

FAANG on the other hand all get their hands dirty in deciding what content people get to see and what not, which would largely be a non-issue if there was mainstream competition, but there isn't, so rather than change their behavior and support/make/demand alternatives, consumers (including politicians) want Big Brother to step in, somehow forgetting that rarely solves anything and will simply consolidate more power with those who already have it.