The whole discussion of pros and cons of the prenup is kind of off topic. The discussion is following rebbeim/daas Torah even without agreeing. Once it’s come up, though…
the prenup is designed to help an already “divorced” woman (i.e. divorced in the legal sense or practical sense)get her get and allow her to remarry.
In other words, it’s not designed to deliniate the marital and post marital obligations as a kesubah is, it’s designed to deal with a scenario in which the marriage ends and the spouses are acting spitefully and maliciously towards each other. Quite a negative thought to start a marriage with.
This is PAA’s point, I believe, and popa’s rebbeim’s point as well. In fact, it seems very much the issue the BDA itself grapples with when they lay out their arguments why a couple should sign it.
One can argue that the benefits, preventing the malicious actions, outweigh this negative, but again, this is where daas Torah comes in, where we accept that our rebbeim are more tuned in to the ratzon Hashem then we are in being machria this shikul.