"Population Bomb" was not a scientific consensus at any time. It was controversial, at best, in its day and has always faced criticism. Ehrlich was a scientist but not of the type qualified to hold forth on the subject, and he did not perform research that would have strengthened his projections, none of which came to pass. His book is pop culture, not science.
https://en.wikipedia.org/wiki/The_Population_Bomb#Criticisms