What attitude can you expect from rationalists towards those who decide to believe in claims without requiring evidence or justification? The moral high ground which you seem to think exists for you, does not.
Philosophy does not require evidence. Philosophy does not require justification. In fact at times it’s best to remove those from your philosophical thought experiments in order to better understand some principle or thought.
Rationalism as a philosophy isn’t without its faults. And many lovely arguments have been made around it. Keep that in mind.
If you're using the term in a more general sense, then social science provides evidence for the efficacy of various Buddhist practices (e.g. mindfulness). I know the state of affairs in the social sciences are suboptimal (e.g. the replication crisis) but it's the body of knowledge we have to work with now.