If he prefers to live his best years lactose tolerant and die earlier but having lived the way he wanted as opposed to living a mediocre lactose intolerant life for longer, then it could still be a success
Effects wore off after 18 months I think. He explains in the video why it was expected.
He took the pills 6 years ago still not killed by cancer. And of course this is n=1. The first thing he says after taking the pills is "Lets hope this does not kill me" :D
God only knows if he's introduced a carcinogenic gene mutation, or if the effects will last. This is the exact thing proper studies examine.