Watched my uncle trash talk Catan once at a family thing, said it was just moving little pieces around. That kind of comment just sucks all the fun right out of the room, same as your boss did. Some people really cannot stand seeing others enjoy simple stuff.
Read a blog post once about why people mock simple hobbies. The writer said it's usually because they are scared inside. Seeing others enjoy something basic makes them doubt their own life. Your uncle calling Catan just moving pieces is a CLASSIC example. They need to put it down to feel okay about themselves. It's a really TOXIC way to handle jealousy.