I actually have on this one. It was a decent opinion piece (if a little dated). It also appears the Media Bias/Fact Check website reflected the criticism and has made some changes since 2018.

For anyone only interested in the bit about the Media Bais/Fact Check mention.

“ The armchair academics

Amateur attempts at such tools already exist, and have found plenty of fans. Google “media bias,” and you’ll find Media Bias/Fact Check, run by armchair media analyst Dave Van Zandt. The site’s methodology is simple: Van Zandt and his team rate each outlet from 0 to 10 on the categories of biased wording and headlines, factuality and sourcing, story choices (“does the source report news from both sides”), and political affiliation.

A similar effort is “The Media Bias Chart,” or simply, “The Chart.” Created by Colorado patent attorney Vanessa Otero, the chart has gone through several methodological iterations, but currently is based on her evaluation of outlets’ stories on dimensions of veracity, fairness, and expression.

Both efforts suffer from the very problem they’re trying to address: Their subjective assessments leave room for human biases, or even simple inconsistencies, to creep in. Compared to Gentzkow and Shapiro, the five to 20 stories typically judged on these sites represent but a drop of mainstream news outlets’ production.”