it explicitly addresses the baseless accusations of internal bias impacting ratings.
that's the very point of these independent studies.
if mbfc checkers or other fact-checkers allowed their biases into their ratings, those findings would differ from other news fact-checking sources that managed to rate news sources more objectively.
since their findings range from very similar to nearly identical to other credible news fact-checking sources and importantly there is still zero evidence of their "own bias" affecting their ratings, there's no base for the accusations.
just rilers rilin'.