And does this unfairly paint them as less agreeable than they would be if you presented what they said with a normal voice?
It depends on how stupid the idea is and whether the originator of said idea should be expected to know better.
For example, at my employer there was a senior engineer that made the FEA engineer waste a month trying to fix a design that would never work, simply because senior engineer wouldn’t spend 2 minutes drawing a free body diagram. That level of stupidity is deserving of mockery