No one who isn't in the Fox News spiral will listen or care.
I seem to recall seeing the stat the other day that Fox News' viewing figures are higher among Democratic voters than NBC.
Ah, here we go:
twitter.com/ggreenwald/status/1489258034865971205
It seems to me that those in the US who refuse to watch Fox might be the ones in the echo chamber... Getting much visibility of the attack on women's rights elsewhere? 
After all, other channels aren't letting troublemakers like Kara Dansky or Posie Parker on.
Or Glenn Greenwald there, who continually justifies his appearances on Tucker Carlson with his view it's the best way to get information out to the most diverse audience who may be unaware of an issue - precisely the opposite of "shouting into an echo chamber".
From those stats, it seems like going on Fox is actually a great way to reach the viewers of other channels, most of whom don't only watch them.
I don't have any love for Fox, but I do have scorn for the others - as far as I can tell anyone relying on US mainstream TV but not watching Fox too is going to be missing a hell of a lot of the picture, due to the other networks' incredibly studied blind spots.
Including the blind spot of thinking that Fox is only reaching a "right-wing echo chamber"
Now, as you can see in the third tweet, there is obviously a huge ideological split. But that data it can be reconciled with the first poll - the third one really exaggerates it because it's just plotting "people who name each as their main source of news", not all viewers.
That sort of open-ended question is just inviting some sort of tribal declaration, so no decent Democratic voter is going to want to say "Fox News" to that, even if they are watching it...
"93% of people who cite Fox News as their main source of news are Republicans" is not the same statement as "93% of people who watch Fox News are Republicans".
Posie is reaching a hell of a lot of Democrats and independents by appearing on Tucker Carlson.