Yeah. I listened to this a long long time ago and Matt Walker explains everything

Basically blocks your DMT, then when you stop smoking, that DMT block breaks and your dreams are actually more intense that normal until your body recalibrated the DMT.

In cases of Alcohol, you actually don't sleep

https://www.youtube.com/live/pwaWilO_Pig?si=zVX7c3aSHKJ6W8qe