Was asserted so often and so widely distributed?

1) Does "was asserted so often and so widely distributed" mean "was stated categorically and (the 'research')was widespread"?
2) Does "that it became the “urban legend” that Americans do not eat GMOs" mean "that it (that Americans do not eath GMOs) became a fairytale"?

Context:

Needless to say, I was dumbfounded by this question because Americans have been eating GMO foods since 1996 and I could not imagine where this idea came from. By asking around, I discovered that this information is publicized extensively by TV personalities and on social media. Apparently, several Chinese reporters traveled to the US and enquired in supermarkets whether they sold GMOs, whether people knew that they were eating GMOs and whether they were for or against GMOs in the human food chain. They received variable answers, of course. Some Americans don't care, many don't know and some object to eating GMOs. Some opinion polls show that many Americans would like GMO-containing foods to be labeled. However, it is known that people's answers to questions in opinion polls are highly dependent on how the questions are posed and whether an explanation is given before the question is asked (PEW 2013). According to a 2006 study carried out by the PEW Charitable Trusts, 58% of Americans were unaware that they were eating foods with GMO-derived ingredients. Somehow, the “research” done by the Chinese reporters who came to America was asserted so often and so widely distributed that it became the “urban legend” that Americans do not eat GMOs. As a scientist who has been involved with the GMO issue for 15 years, I can state quite categorically that most Americans eat GMO-derived foods nearly every day! Furthermore, Americans have been eating GMO foods for 17 years, so far with no ill effects as far as we know.