The mbfc site should not be used for anything. It’s just the subjective opinions of the site owner (who is misleadingly talking about “we” and “our” in his methodology page), aided by a few unknown volunteers who do some of the “checking”. The site claims to be objective, but there’s been enough examples to show that it isn’t (fe, it says that Fox News is as trustworthy as The Guardian or that CNN is somehow center left).
The so called methodology that is used, is just a lot of words that boil down to “several facets were checked by a human and that human gave a subjective rating to each facet, we then count up those subjective ratings and claim to be objective because we use a point system”.
For checking the trustworthiness of a source, I’d say that the mbfc site is about as useful as using CPU Userbenchmark for chosing a CPU. Yes, it’s easy to read and more convenient to use than other sources, but it’s also a load of horseshit and unless you drill down into the underlying “data”, you’re just going to draw the wrong conclusions because of how misleading the site is.