its bullshit. I used to believe it until i realized my 'ed' was simply performance anxiety induced by over analyzing nofap, p*rn and under pressure with new women. All of which was caused by my own beliefs, which framed my feelings towards said interaction.
I have done the 90 day nofap challenge twice, and can confirm it made no difference whatsoever. It's more so for self-development if anything.... the ironic part behind nofap is you will cointribute your success to it, and start to believe the outcome of your interaction was behind nofap. When you relapse you will develop a guilt, and conscience towards having to quit or else you wont perform. It's a spiral of bullshit in which you convince yourself that nofap is the reason why you can perform.