Rather than hearing about it from the internet, you might spend some time talking with those individuals who do experience it. They're often reluctant to talk about it -- especially if you're likely to respond with some variant of "Oh, that's not really so bad".

Most people are nice in this world, but there are enough non-nice people that everybody in some marginalized group gets subjected to it -- often every single day. Often it's small, but a small thing every day adds up. And being unable to talk about it for fear of being told "it's not so bad" is, itself, just one more small thing. And that means that some people who think they're nice aren't as nice as they think they are.