Common sense is a wide concept. Maybe we need to narrow it down some.
If I look at myself and my friend we both lack common sense but in different ways. She seems to have a 6th sense about people that I lack, she is not even normally suspicious, it's like she is a mind reader sometimes with others. Myself, I'm gullible as heck. I have to make an effort to understand people are capable of lying and stealing.
But she lacks something I take for granted, knowing cause and effect. Like, if she buys new shoes she will not be able to pay a bill. For me that is simple. She still doesn't seem to connect that what she does now will cause problems in the future.
Then there are simple things I never learned, like making coffee. I mean, who can't make coffee?
Also, systems that have the slightest complexity might trip me up. I can handle standing in line and for goods. Simple. But here you might have to purchase a card or token for some goods like cigs which you then go use in some machine. I'm glad I'm not a smoker, I'm lost when they mess things up like that.
There are things I should know by now about how people work. There are things I should know how society works. And other systems. And those dang coffee makers.
But us who are lost with the big picture tend to be really good at some areas. I wouldn't want to lose that just to be fairly good at "everything". If others want to look down on me, fine. That would be immaturity on their part.
I hang out with people who are everything than average. They have some strong and some really weak sides. It makes life interesting. I wouldn't have it any other way.