Perhaps applying a blanket statement to straight people isn’t a great idea either? I’m straight but think it makes complete sense for young people to learn about relationships of all kinds at what ever age they start learning about relationships. My personal approach is to stick with gender-neutral pronouns by default and to treat any relationship between consenting adults the same as any other. I’m lucky enough to live in a place where this is mostly normal and only the crazies have an issue with it. I also don’t ask toddlers about romantic partners.

As a side note: it’s not uncommon for seniors in Korea to ask to see, and then comment on, the genitalia of young children (not necessarily sexually). A practice which is dying off but still exists. Point being that I acknowledge there are still all sorts of different social norms out there in different places.