The conditioned response that you're talking about is typical in a culture where we're taught to trust in science. I'm not saying that anyone should believe in astrology (I don't), but having spent the last few years looking into a number of topics similarly treated as esoterica, my understanding is that we're often unaware that science as a discipline is not dogmatic in what is possible. But human bias is probably its weakest element. How it has historically impeded our ability to understand certain phenomena (and continues to do so today), combined with our amazing ability to forget how wrong we can be, has convinced me that being open minded is not just politeness, but an imperative for anyone who wants to truly understand what's going on.

Most of what we think we know as individuals is actually just a set of beliefs (often never tested) to which we heuristically assign some probability of truth. When you really start to dig yourself, you often discover that scientists, like any humans, are not immune to religiosity. They believe some thing is possible, or that some other thing is not. Those beliefs tend to color how the research is done. It also seeps into the culture of a society that has learned to so overly rely on "what the science says", that what it remains silent about is mistaken as untruths. Research must start with a hunch, a belief. But beliefs are often consensual and if the consensus is strong, it can be very difficult for a competing theory to hint at a possible different direction, even with supporting evidence. Our history books are full of examples. We set out to study a misunderstood phenomenon, but because there is a strong consensual belief that it must have certain properties, we approach our explorations with those premises as established truths. When we get stuck, we have to wait for an entire generation to die off to reorient the research (as Max Planck remarked).

Having observed the above in my own diggings into certain topics that (luckily) have some scientific documented intersects, I'm now reeducating myself to have less of the conditioned response of taking my own beliefs (e.g. astrology is probably BS) too seriously, when evaluating people's intelligence if they believe the opposite.