@HGohwell I do consider BL as unrealistic fiction when consuming it, and most people I know around my age (upper 20s-30s) are also aware of its tropes genre when they read it as well. The stereotypical "fujoshi" behaviour we see online is often new fans of BL who are still young and discovering a genre that they assume is reality and not fiction.
My friend, a consumer of BL, (cis male, bisexual) calls it "a genre that's very similar to shoujo romance, from the types of couplings like teacher x student, to the wild tropes like wall slams". We all don't consider shoujo manga to be realistic, and he similarly compares BL manga to shoujo manga.
BL feels like that middle ground between shoujo and josei manga. It has the unrealistic flappy romance adventures that shoujo would have, but characters would often be older like the office ladies from a josei manga. Considering that it is technically considered a genre "made by women, for women", this description of BL fits well as a road between girlish shoujo and mature josei.
If I wanted realistic LGBT stories, I would specifically read stories that are tagged LGBT, not BL. I consider BL to be it's own genre.