Disclaimer: this is purposefully obtuse.
Other effects in the game which explicitly state they kill you:
Shadows, succubi, massive damage, death saving throws, beholder death ray (notably not even their disintegration ray kills you), power word kill, vampires, mind flayers, night hags, drow inquisitors.
Clearly, if they intended for disintegration to kill you, they’d have said so. Since specific overrides general, and there is no general rule that disintegrated creatures are dead, I rest my case. QED.
It’s like this for all TTRPGs. Someone always be trying to rules lawyer away someone’s fun. 😎
I actually love rules lawyering, but it has to be done away from the table, and done with a certain amount of good faith. And don’t get mad when others rules lawyer you back.
In 7th Ed 40k, I found a way to make the Tau Stormsurge to be even more ridiculous than it already was. It clearly conflicted with RAI. I had to talk it out with another Tau player, who was a real lawyer, to find a way to invalidate it. He had to pull out actual lawyer tricks of carefully reading the rule to disentangle it, and he agreed it wasn’t at all obvious.
But I never played with that interpretation, and never intended to. Tau players already have a reputation for playing like dicks.
Hey, that rules-lawyering is someone’s fun!
Rules-lawyering rules lawyers is my fun!
It’s like this for large parts of human life; you just hope that no lawyer ever gets wind of whatever thing is being done.