Because it's not a fact lmao. The commenter is only 33. At no point in their life has having roommates meant you were gay. Maybe another 20+ years before them, and if you were a man in your 30s or older with a roommate. But that's because the assumption is generally that if you're living with someone in your 30s, 9 times out of 10 they're your partner. Most people find a long-term partner by then that they live with.