The formula says you're lower risk if you use more types of credit responsibly.
And yet it says you're higher risk if you had more types of credit, but eliminated one by paying it off. Literally doing the thing you're meant to do.
And we all know that they can never alter the formula, so I guess that's that.
We're talking about why the formula is very stupid in certain cases, so "it's like that because the formula says so" isn't really an argument. Like... We know.