Society always attempts to control behaviours that it deems harmful to the rest of community.
You think its normal or natural for a 50 yr old man to be attracted to a teenager? People react badly to this because they can tell it means something has gone haywire.
Men who do this need to realise they have to fix something in their brain - some kind of sexual trauma - its not actually a healthy response. Its not healthy to tell yourself its fine. Its not healthy or normal to see other people as objects in general.
Teenagers know nothing about the world, and its super easy to manipulate them or abuse them - and obviously thats part of the attraction for a sick mind.
My mother never protected me, and I experienced that 100%. Its just a look, but this mother knows what it MEANS