It's much worse than they havent played games at all. They would probably object and say that they do play games, they've played some mario cart that one time, and they play mario party and some monopoly game with their children. They almost certainly have played at least a few brief moments of their flagship games at a show or something.

They assume their own experience is more or less what everyone else has, including their players. A sort of dabbling, disinterested experience, flowing from one piece of content to another.

It is worse than not having played games at all because when people around them take on the task of making games with intensity and zeal and solemnity and great care, they can roll their eyes and think "it's not that serious, nobody really cares about this stuff". When people have passionate arguments about creative direction they feel they can see the bigger picture and rise above the petty squabbles by saying that the artistic direction doesn't matter. They know it doesn't matter, because it doesn't matter to them, and to all the other people who, presumably, are like them.

I think that they are wrong, but I think the task of explaining to them why they are wrong is like trying to teach a devout atheist why religion matters. It will be a long and hard uphill battle and in many cases likely utterly impossible.