While Russians had a part, Trump was not completely propped up by Russian propaganda support. It's not unreasonable that many Trump voters had no or little contact with fake profiles run by Russians, and were not significantly influenced by it.

But we can't really know that without tracking down all of their activity.

I abhor Trump, but he had plenty of organic and authentic support here in America. I don't think we'll ever find a smoking gun that says "Trump wouldn't have been president or won the primary if it weren't for this one Russian effort" (but stranger things have happened).