I don't think that's entirely true. I was once a denier, even with more than a decade of science research experience under my belt. Eventually I actually made the effort to take a hard look at the science, and I realized that every denier talking point was built on half truths.
A significant problem is that scientists are not in the business of public relations. A scientist with integrity will be quick to point out uncertainty and tend not to make sweeping, sound bite conclusions. The lack of sound bites from the scientific community has been used to the advantage of denier propagandists. Understanding the data requires a certain attention span, but corporate talking points and propaganda do not.
For people with little understanding of science who have bought into the corporate propaganda, yes, there is little chance they will change their minds. It does take a certain amount of patience and/or scientific understanding to comprehend the data, even data as damning as that surrounding climate change.