Never found much of a benefit from DHEA but it is popular in many TRT clinics.
I wouldn't take anything if I competed in any sport tested by USADA. Even then, if it isn't a medication and controlled you could accidentally take something thrown in a supplement since those are not tested by any manufacturing overseeing body. I don't believe most these guys who are taking oral steroids or SARMS and say they didn't know better but am sure it does happen.
For example - Jon Jones, could have been the best ever without an asterisk beside his name. He is/was the GOAT (never been beat except one bad call for an illegal shot) but had too many issues and no one will ever convince me he was taking Turinibol and other PCT drugs without realizing he was doing something wrong.
Allistair Overeem is guy that comes to mind when USADA turned their game up and he went from 265 ripped to looking somewhat mortal. Still huge and dangerous but people didn't gasp after he cut weight to make 265 and step on the scale.
These guys can't take anything without being worried they will be testing positive. I can't recall the year but they changed their testing techniques and got better at catching designer drugs - it was right around when GSP retired.