Someone else might have gone nuts and killed themselves
I hadn't thought of that, what would happen? Would Picard reset back to the beginning of the download and have to live everything all over again. Or regardless of the method of suicide (let's pretend it was explosives) does he just continue on as if nothing happen.
He can't actually die, because he is safe and sound lying on the floor of the bridge.
Maybe if he killed himself in the download, he'd simply wake up.
When the Enterprise cut off the beam, Picard almost died as a result. It's possible that if Picard tried to commit suicide on the planet that the beam would be interrupted, and Picard would go into cardiac arrest. Do you find this plausible?