I'm Asian, 37, and have double lideye lids. As a little kid in the 90's I remember other kids(mostly or all white I think) repeating this line to me "Chinese, Japanese, Look at these". When they said the "look at these" line they would pull their eye lids sideways. It didn't matter that I had double eyelids, all Asians have monolid and that's that.
Honestly I didn't understand why that was being said to me and just found it kind of funny back then, but that was a completely different time. Nowadays I get very annoyed when people still try to associate all Asians as having monolid eyes. It's common, but it's also extremely common that we don't have it either. It already plays a role in Asian self hating, casting calls asking for one or the other is only making things worse.