A spiral effect ensues: because so few persevere and make it through, they remain invisible at the top. The opposite effect can be observed in women’s sport. For a long time, this led to stigmatisation of some games women play, now receding and in fact being replaced by celebration.

At the other end of the road, there are other inhibitions. As was noted this week, coming out looks like a first step, but is in fact a last. A young gay sportsman is likely to have agonised for years until arriving at a point where the price of hiding his true self was taking a greater toll than whatever it cost to reveal it. You could hear this clearly in Cavallo’s story. Even then, some still baulk.

Only recently, decades after Fashanu and Roberts, sport has begun to understand and allow for the peculiar risk it poses for the mental health of its stars. For a gay footballer, this redoubles. You’d think this new awareness would bolster anyone in Cavallo’s boots. But even if and when he has reconciled all within the club, once he opens the doors he would be met by the monster of social media. This is the change for the worse since Fashanu and Roberts.

There is a parallel with racism in sport. For all a club and code might do to tackle it, they can’t tame the anarchic and bigoted social media world. It drove Eddie Betts up the wall. It is not hard to imagine that this is the bridge too far for some gay footballers.

Are the AFL and its clubs welcoming enough? They think they are. But Monash behavioural scientist Erik Denilson notes research that draws a distinction between attitudes and norms. A sports body might adopt enlightened attitudes - supporting Gay Pride matches, for instance - without underlying norms within the club, like language, changing. Because gay voices are never heard, the language is never challenged.

He likens it to the way you might speak with your mates, but not to your grandmother. The Taylor Walker case is one prize example, Collingwood and Heritier Lumumba another.

“Our own research has found the AFL has done less on the issue of homophobia than any other major sport in Australia - or globally,” Denilson wrote earlier this year. Though it has a polemical ring to it, the fact is that still no gay AFL player has emerged cannot be mere happenstance.

So much of the spasmodic conversation about gay men in professional sport is conjecture because so few authoritative voices are heard. Josh Cavallo might have relieved himself of a burden this week, but he also gave sport a gift.