Industralization and urbanization started way before(18th century) - and we didn't see dramatic improvement. It improved basically people nutrition and made their lifes better no doubt - but modern medicine - is responsible for 20th century population revolution.
Has Africa industrialized and urbanized? Of course Not - and yet it has seen dramatic population increase. So your whack theory is very old theory - yes agricultural revolution - led to better nutrition and improved pop - and so did industrialization - but birth of modern medicine - esp antiobitics in 1928 was the key point.
Industrialization/urbanization encompass modern medicine.