Did you know that 98.2% of statistics quoted by people online are simply pulled out of their ass? Did you know that people are less likely to be open about their sexuality when they'll face communal scorn and exclusion, or often physical harm, for openly expressing it?

The number of people that would identify as queer is certainly higher than 5%, and that doesn't even include all of the closeted or self-denying people that have been indoctrinated by religious bullshit or simply growing up in a conservative area.

That the number to which you default is 95% is a crystal clear example of the sort of heteronormativity they're referencing.