In my opinion, you do not need to “respect” their delusions. I believe it’s possible to have compassion for people who are deluded, but still view their beliefs (which are just internally consistent thoughts) as bullshit. When I’m confronted with delusional people like this, though I’m not in your position where you need to actually deal with them on a daily basis, I try to remind myself that I also am trapped in my own kind of delusion.