"The idea that something may be true, valuable, or good merely because it is common sense or inherited tradition is anathema to them"

This is reasonable though. Tradition and common sense suggest value perhaps more than rationalists think, but if tradition and common sense have value, there is an underlying reason.

There is also value in the abstract sense, meaning tradition can have value for the consensus and social understanding it causes.

Like, maybe Christmas as understood for Americans has no value. But the fact a Christmas exist does result in families getting together and provides a cohesive context for the winter season across pop culture, and that can have downstream value.

But even if we don't know the underlying reason, they are still valuable by dint of having survived for so long