everybody is. Every human. everything humans create, all has a bias. Worse… that might not even matter because their process has got to basically be “we do a spot check of articles to make sure they’re factually accurate and then we fit them where we thing they fall on the US political spectrum”
The reality is there’s no way to know how thorough they actually are, and for most publications- even “small” publications- it’s a bit of a joke to think five to ten articles is enough to determine reliability. other similar groups like Allsides and Ad Fontes have hundreds of employees/contractors reviewing outlets and their analysis is still remarkably circumspect.
MBFC has nine employees, including the founder. Nine.