He endorsed Bernie through 2023 when he (accurately) noted Sanders shifting away from anti-war/anti-imperialism positions, which seems to be Greenwald’s #1 focus. He was opposed to what he saw as the Biden admin’s role in perpetuating the Russia-Ukraine conflict and Biden-era “counter-disinformation” initiatives, which he is unsurprisingly opposed to. He maintains these positions under Trump while conservatives have moved against them; they are not “conservative” positions.
I’m not opposed to people hosting interviews with political opponents, and reasonable people shouldn’t be opposed to that either.
By 2023, it's not "hosting interviews with political opponents" - it's obvious that giving a voice and publicity to people like RFK Jr. is actively harmful to society. Freedom of speech means we don't throw RFK in jail, but no one has to publicize his views.