Why did skeptics give exoplanets special treatment?

With all the news about exoplanets these days, including the announcement of the discovery of one which could, theoretically, support life, we should remind ourselves that as recently as 20 years ago we had no evidence that such things existed in our universe.

Of course, people had assumed they existed for a long time. Speculations about a "plurality of worlds," corresponding to exoplanets in some interpretations, apparently go back to Epicurus and his Roman expositor Lucretius; and the idea has shown up in fiction from time to time before the 20th Century. (Voltaire provides a well-known example.) When the genre of science fiction emerged in the 20th Century, imaginative writers ran wild with the idea of exoplanets and made it part of the popular understanding of the universe.

Yet, as I've pointed out, until the 1990's we had no evidence that such things existed. The idea of exoplanets before 1990 or so belonged in the box of what skeptics would call "extraordinary claims," sometimes also called woo-woo; and it shouldn't have gotten out of that box and become scientifically respectable without "extraordinary evidence."

But curiously, to the best of my knowledge, no skeptic before 1990 categorized belief in the existence of exoplanets as woo-woo. Skeptics seemed to have taken a faith position in favor of exoplanets' existence, in other words, despite the fact that exoplanets play a role in other residents of the woo-woo box like Mormonism, Scientology and some UFO cults.

What accounts for exoplanets' special treatment before the evidence came in? Because of a non-empirical commitment to the idea based on materialist philosophy? Or because some high status skeptics, like Isaac Asimov and Arthur C. Clarke, had scientific backgrounds and wrote science fiction about exoplanets? Or because some scientists with the related evidence-free belief in extraterrestrial intelligence, for example Carl Sagan, had aligned themselves with the skeptic community?

It makes me wonder what other ideas about reality we've wrongly categorized so far.