Well, the implication is still that hostility is somehow less serious or meaningful when directed at white men... I think you can imagine why that would make us uncomfortable.

Or worse, they're implying that minorities and women are all insecure and thin skinned which is the very behavior and thinking they're ostensibly trying to prevent.

They probably have more data on minorities than on insecurities. Some ad networks can tell your gender and ethnicity with reasonable accuracy (especially in the aggregate). Stack Overflow might be affiliated to one of those, or use data mining algorithms similar to what they use.

They also run polls among their users, I believe. It's easier to ask about gender/race in a poll than about unspecified insecurities.

Because the community doesn't identify with them? Specific insecurities isn't something that can be addressed at a platform level but general ones like "am I a member of the group of programmers because I am black/female/gay/trans" can be better targeted. So they probably won't help everyone by doing this but they can help a large group of unserved people.

We don't need to stop at group-level insecurities, we can just be kinder and more welcoming to everyone, thereby addressing _all_ insecurities. This has the added bonus of dodging the entirely unnecessary, divisive, and toxic political fights about which groups are the most victimized.