He could have been upset that he screwed up, and distracted from what should have been an unalloyed celebration.
This. Whether he thinks the furor over the shirt was silly or not, whether he is a misogynist or not… the one thing you can be almost positive of is that he is very passionate about this project.
People working on space missions dream of days like the ones that have just passed. They work for years for a mission that might fail in an instant or in sudden silence and leave nothing whatsoever to show for the effort and money spent.
These people are about as passionate about their work as it gets. Mission days, landing days, etc. literally are the highlight of their professional career and in some cases their entire lives… and they know that is true for everyone else there.
Even if he doesn’t get the problem with the shirt, he’s almost certain to have gotten the message that he did something that detracted from that dream, from the joy and celebration and wonder… it was possibly watching an event day like this that inspired him to go into the field in the first place, it certainly was for many others.
So even if he thinks the shirt is otherwise fine, there’s an extreme likelihood that what you saw there was genuine remorse at having tarnished a special day for his team and his colleagues. It’s very UNLIKELY that what you saw was a man reacting to having been somehow bullied or browbeaten.