I’ve been around a while and I never heard this interpretation up until very recently.

Ever since same-sex marriage passed, certain well-funded bigot groups have been explicitly and deliberately engaging in a “divide and conquer” strategy for taking down progressive movements. First they pushed transphobia as a Feminist quality. Now I guess the whispers are that bisexuals are trans-exclusionary, which in turn is stoking biphobia too? Don’t fall for it.