They sure did ignore the light barrier. But I think they all heard of relativity, and a light speed limit, and chose to ignore it for better stories. Similar to how Asimov often ignored the fact that most worlds in our solar system can't produce life. If you want people to meet aliens, it's easiest to ignore science.
Or Edgar Rice Burroughs.
https://literature.fandom.com/wiki/Barsoom_series
The known science of the time prevails, and then you stretch it through imagination.
there have always been scientists who were more optimistic and others who were more pessimistic about life on other planets in the solar system.
Isaac Asimov was more scientificly accurate, and wrote in a better informed era, than Edgar Rice Burroughs, so Asimov's stories are closer to being accurate - then and now. - than Burroughs's are.
Asimov wrote the
Lucky Starr novels for young readers to educate them about the solar system. And if I remember correctly, Asimov added notes to later editons of them when they were proved inaccurate.
Asimov in
The Currents of Space briliantly used a contempory scientific theory to justify a character being able to predict which stars would go nova, setting off the murder mystery of hte plot. But that concept is no longer valid.
E.E. Smith's
Lensman series brilliantly used a scientific theory to enable Kimball Kinnesson to deduce which galaxy Boskone came from, but that scientific theory is obsolete and abandoned now.
Larry Niven's first story, "The Coldest Place" was scientifically valid when it was sold, but scientifically osolete before it was published a few months later.
And some science fiction fans alive today could tell you how disappointed they were by the discoveries of the conditions on Mars and Venus in the early space age.
