Someone told me that it was obvious to him (and he got someone else to agree with them) that all men today are a safek zav. Meaning, a zav is someone who had an unusual emission from their body (Leviticus Chapter 15). Since we today don't know what that entailed exactly, who knows if they never had one. They were saying everyone has the stringencies of a full zav, who needs seven clean days and offerings (similar to how women accepted upon themselves safek zava status). Since we don't know what to check for, people are stuck in this state.
Do any poskim or seforim say such a thing? I find it incredibly hard to believe. I feel the emission was very abnormal, and much easier to notice, and is nothing like a zava at all.
This conversation came up with regards to going to har habayis, which is forbidden for a zav (Kelim 1:8). My understanding is the poskim who discuss going up there just say to be careful where to go and to go to the mikveh (presumably for tumas keri). If men were safek zav, a mikveh alone wouldn't help...