I'm sure McCarthy really was just joking when he said he'd hit Speaker Pelosi with the gavel should he ever be so fortunate to rise to that august position. I'm sure he was. I don't think he'd ever do it, do you? Okay, forget that question. It is the Republican Party we're talking about here, so who the hell knows, amirite?
Regardless of whether he was joking or not, there is a real problem with telling such jokes, and it's called Prejudiced Norm Theory. The theory states that for people who are relatively high in prejudice against the targeted group, disparagement humor will increase the tolerance for prejudicial acts against that target group. In other words, people who heard McCarthy's "joke" will be more tolerant of abuse meted out to Pelosi and other Democrats.
Studies suggest that when a prejudiced person overhears a joke targeting the group they are prejudiced against, they are more likely to act on those feelings at their next opportunity. So, the rank and vile MAGA Nation member hears McCarthy's "joke" and it encourages them to engage in a real attack on Pelosi or other Democrat. It might not even be the rank and vile, it could be a Congressional backbencher like Maddog Marjorie Taylor Greene or Loaded Lauren Boebert who take the shot at Pelosi.
The prejudiced person hears the "joke" and feels understood, accepted, encouraged even. They feel like their bigotry is justified and more widely accepted than it is. It coarsens our society. It makes acting in aggressive ways against those we disagree with seem more acceptable than it is and more likely to occur.
It is dangerous for people like McCarthy to fall to the temptation to tell such jokes. We should expect better of our elected leaders, but the Republicans don't. In fact, they do the opposite. they encourage such behavior, and we are the worse off for it.