I think it's abnormal and the kids are likely underdeveloped due to lock down isolation. Waking your parents up crying when you're a teenager because a youtuber died? Get that kid on a sports team, fast.
I'm not sure if there is an undertone of a joke here. It doesn't seem that way to me, but if that is the case then that in my head would be the most forgiving scenario. Even then your comment feels accusatory, judgemental, and the sort of thing a bully might say.
Please try and realize that people are different. Not conforming to the "ideal" construct of a child in western society might not be the worst thing. Diversity in thought and opinion does not _only_ come from race and gender, it also comes from nurturing thoughts and perspectives in our own kids that might not align with the norms. This doesn't mean saying everything is great, but being an adult, and discussing various facets with them rather than shut things off.
It's not "underdeveloped" to have emotions, or to be sad when someone you relate to dies. I used to think it was dumb that people cried when John Lennon Died; then when Elliott Smith died I "got it."
I think it's healthy for your empathy circle to extend beyond your immediate family.
Please try and realize that people are different. Not conforming to the "ideal" construct of a child in western society might not be the worst thing. Diversity in thought and opinion does not _only_ come from race and gender, it also comes from nurturing thoughts and perspectives in our own kids that might not align with the norms. This doesn't mean saying everything is great, but being an adult, and discussing various facets with them rather than shut things off.