It seems to me like an important thing about individual taboo facts is that it’s not particularly advantageous to be correct on them, most of the time, because you can’t publicly work with others on the basis of those facts.
Compared with most other facts that are similarly not widely believed, but are not taboo, it seems clear that taboo facts are far more advantageous to know. That’s because most uncontroversial not-widely-believed facts are very unimportant, while taboo facts tend to be highly important and have wide implications (just consider atheism, or belief in evolution, when those where highly taboo: it made everyone act on the assumption that they were false), even if it is often not easy to directly act on them. Individual knowledge of those facts is a necessary requirement for un-tabooing them and making them common knowledge.
Compared with most other facts that are similarly not widely believed, but are not taboo, it seems clear that taboo facts are far more advantageous to know. That’s because most uncontroversial not-widely-believed facts are very unimportant, while taboo facts tend to be highly important and have wide implications (just consider atheism, or belief in evolution, when those where highly taboo: it made everyone act on the assumption that they were false), even if it is often not easy to directly act on them. Individual knowledge of those facts is a necessary requirement for un-tabooing them and making them common knowledge.