I agree with this. There is at least a common baseline for the "fun" factor in every single game, and we could consider that as the objectively fun item, enclosed within any game. That is why there are game design best-practices, trends and courses.
Everyone is different but i think that no-one can be completely different from another person, because we all share at least a subset of preferences/experiences/backgrounds, and that means that a common ground can be found.
Space Invaders is fun. Objectively.
Everyone can see why it's fun, and maybe you're not interested in games, but that doesn't make it less objectively fun.
Nowadays games are way more complicated, evoking a way broader spectrum of emotions, so it's maybe impossible to make something universally "fun".
Maybe "fun" isn't even the correct word anymore, maybe it can be more correct to use the word "enjoy". What people enjoy is, of course, personal. Still, you can group people based on their shared interests, and create something appealing a wider audience. That's the objective part.