Exactly. I had a hilariously pointless meeting with a (well-meaning, let's be fair) nutritionist at SCCA / Fred Hutch who gave me generic "eat less red meat and more vegetables" advice, but that was all she had, because it was so screamingly obviously genetic. Diet won't make it go away.
My son’s diet is terrible…but he doesn’t have much incentive to eat better when he saw what I endured. I think in his mind if he has to start scopes in 6 years to fend off cancer, why not eat what he craves, now. I’m more worried about the other poor diet ailments that he could encounter, sadly.