IDK if he mentions it later in the video, but he missed an absolutely crucial revelation in the opening scene (see Moloko Plus):

The Korova milkbar sold milk-plus, milk plus vellocet or synthemesc or drencrom, which is what we were drinking.

Gets you ready for a bit of the old ultraviolence, indeed. Keep in mind this was written sixty years ago.

• WARN, verb - "to give notice of approaching or probable danger"

a) motion inspires adaptation; hence giving notice of approaching danger (death) for those being moved (life).

b) being (life) implies exposed to injury (inception towards death); hence temporary shelter (living) within ongoing danger (process of dying).

tried to warn

Suggested warnings tempt those who consent to ignore perceivable danger.