Society has been at war with human puberty since industrialization
Higher quality diets made possible by industrial agriculture cause puberty to come earlier.

Early factories make heavy use of child labor, but society becomes repulsed by this, especially as children are frequently injured on these jobs. So initially the stresses of these factory jobs delayed puberty, but sitting at a desk all day instead made it earlier. And the social pressure grows for kids to stay in school longer, meaning, they spend more and more of their peak hormonal years unable to eatn money or start families. 8th grade used to be like high school. Staying in school after your 14th birthday was optional. Then it was 16. Now it's typically 18.

Anyhow this continues with the ongoing increase of people going to college. Further economic developments push the ability to earn enough to support a family later and later.

All of which is to say, puberty blockers are just a new weapon in a war we've been fighting against biology for over 100 years. The transgender aspect of it is probably a distraction, more parents were probably going to find them to be an attractive option regardless.

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