This is not bro science hog wash in any way shape or form. This is coming from a guy who absolutely hates bro science, but in this regard you’re incredibly wrong.
Primo is incredibly effective at lowering e2, I’ve crashed my e2 on just test and primo with no other compounds thrown in the mix and I know a lot of other guys who are very smart and keep up with their blood work etc who have done the same thing.
There is absolutely no question whether primo will lower e2 and if you truly think otherwise, go head and run some test and primo and post up your labs.