There's a sort of hidden weakness to "losing": it's extremely difficult for people to correctly filter out BS at scale. I'm not talking about on an individual encounter level - BS almost always loses to truth. But the percentage isn't so high that smart and/or successful people never fall for BS in their lifetime. Especially since BS is under evolutionary pressure to be extremely believable. That's a big part of the…
This is an important effect to note. If criticism of an idea is not socially allowed then you cannot rely on mainstreamness as a proxy for truth.
There's also another effect worth noting: if an idea is relies on building blocks outside daily experience (e.g. anything about the large scale) and requires quantification as part of the argument then its going to struggle to propagate (both the guys with the megaphones and your average Joe are bad at thinking quantatively). Incorrect ideas about the dangers of nuclear power being the classic example.