Sometimes I wonder if the general decrease in trust in society affects psychology research:

http://www.niemanlab.org/2019/01/a-gloomy-vision-for-fake-ne...

The Milgram experiment is the most prominent example which might not be possible today because it depends on participants' willingness to obey scientists. The Milgram effect is still real, but it has become harder to measure.

So in this case, when participants are asked to reason based on premises they don't agree with, they might, as you've suggested, refuse. They might interpret the researchers' intent as nefarious, e.g. "if I agree this syllogism is valid the researcher will report that I support the conclusion". This line of thinking is of course absurd, but it comes close to what I've observed that some people believe about scientists.