The criticism looks like most criticism of news media: braindead reporters, selective coverage, etc., pointing to some bias, but not really enough overall to be conclusive. And associated with the same sort of people that would sign a petition to ban dihydrogen monoxide.
IDK, my experience is that news reports are OK for getting introduced to a topic but all the detailed/useful information is in blogs and databases these days.
“Radically centrist” and “unbiased” are mutually incompatible descriptions, the former of which is compatible with propaganda favoring the elite consensus.
I think the complaints about it being liberal are only valid in the context of not being rabidly right-wing.
The fact that "liberal" is considered a pejorative today is testament to that.
I welcome proof otherwise.
Edit: example #1 of "neutral bias": The war on drugs is reported on in a matter of fact manner, and I've heard ZERO editorial comments that point out the insanity and wrongfulness of it. Same thing with the wars, etc.
You can't go out of your way to avoid particular positions to stay unbiased. Going out of your way to avoid particular positions is bias.