It's like anything else, for example the use of mind-bending legal meds or the abundance of required vaccines. Long term studies of something require a few generations. All of these studies draw long-term conclusions from short-term results.
Anything that messes up reproduction will never go away.
“Anything that messes up reproduction will never go away.”
Legal marijuana messes up reproduction?
“Anything that messes up reproduction will never go away. “
How does that relate to the millions of kids born to stoners or former stoners over the years?