"no less than" is a formal way to say "just as much as" or "the same as". When you use "no less than", you want to emphasise that A is equal to B even if this is not obvious or when people often think otherwise. There are some situations where there is subject / verb inversion in a statement. The purpose is to express emphasis in a formal way. e.g. "Only by studying every day will you master another language." = You will master another language only if you study every day. In your case, the sentence is actually quite clumsily structured and hard to follow. There is no real need for "are", in any case, as it would be implied.

"it is no less a product of nature when that structure is ‘isolated’ from its natural environment than are cotton fibers that have been separated from cotton seeds or coal" is a comparison using than it sounds like.