I am guessing we are all going to notice things that feel a bit off or stereotyped (not to mention insulting) when they relate to our own group. I'm a woman, and I've known quite a few in my life, so I pick up on it when every woman seems to be a stereotype I've struggled against, or when none of them are anything like me or women I've known in my life, or when every woman is simply an object of gratification for male characters (and readers).
I sometimes pick up on male characters who seem off too, as in none of them seem at all like most of the guys I've known in my life. I know a female writer--used to swap crits with her--who writes her guys as macho, completely un introspective types who punch people who annoy them. She complains that my guys are too deep and conflicted--guys aren't like that, she says. They tend to only think of one thing at a time and don't agonize over whether the things they do are right or wrong or spend much time worrying about whether they are good people and so on. They just act and deal with the consequences. I'd call her guys the male equivalent of those cardboard women some men write (and bordering on sociopathic), but eh, not all guys are alike. Some probably are like the ones she writes. I'm just not interested in hanging out with or telling the stories of the ones who are, even as antagonists. Even if the men in my books are unusually deep and conflicted, those are the kinds of guys I find most interesting in my own life and in literature.
Maybe we've just known very different men in our lives and read very different books by and about men.
However, it can be easier to miss things that are off or stereotyped about members of groups that are not only not us, but that we have had little intimate contact with in our lives. This is especially true for groups who aren't well represented as writers or as characters in literature (women, at least, have plenty of books written by and for men to pore over to see the diversity of male perspectives, and the same goes for men writing women, though a surprising number seem to have read or remembered very few books by women, at least the ones on many of the SFF boards I frequent).
Empathy is good, but it only takes one so far. For example, putting myself in the place of someone who has lost their sight or become paralyzed, I think I'd be depressed and angry that this has happened. I could certainly write those feelings from my own experiences of being depressed and angry and motivated to find a cure, and I could research the changes in mobility etc..
However, I've been told that plots where a person with a disability is cured, or is seeking a cure, or who feel bad about their disability for the disability's sake (as opposed to simply being resentful of a world that doesn't accommodate it), are insulting and patronizing, written by able-bodied people who don't get it. I have a really hard time understanding this, so I'd not write a story with a disabled person where the disability and their feelings about it, are central to the plot. I haven't even had any close friends or family members who are blind or paraplegic, for instance, and I haven't read many books written from the viewpoint of a character who is written by someone who is.
This doesn't mean I'd never include people with disabilities in my books. The world isn't 100% able bodied. But I wouldn't feel comfortable writing a book that focuses specifically on that experience or journey.
And also, the advice not to write a book that is supposed to focus on the experience of someone from a different group is a good one. I have no problem writing male characters. I like stepping into a male skin sometimes and being a sort of male alter ego. I am also comfortable writing books where different notions of masculinity and femininity are important themes. I don't think I could write a book that is specifically about male bonding, or about the Father-son dyad, or about what it means to be male--at least not from the perspective of a man living in the modern world. At best I'd be copying books that have already been written by men (and probably bringing nothing new or unique to the table), and at worse I'd be a bit "off."