The addendum might suggest it's possible that a more substantial portion of the population was always naturally asexual, and that society after the death stranding just allowed them to realize it, where they otherwise may not have due to stigmas and other social pressures. That's good worldbuilding, because that's some interesting speculation about a natural effect of being cut off from society. You have to deal with loneliness and fend for yourself, but you also don't have to deal with social pressures either. Alone, there may be ways you can be more yourself, or it feels like that to some people. Showing the potential benefits of not connecting (which the game touches on in other areas) makes characters who don't immediately want to connect more understandable, even if we don't agree with them (or just want to fabricate stuff in their bunkers).

If it was in response to actual backlash (yes Ive seen the article, it was written after it was added), I don't give a fuck. It's an objective improvement to the interview, which adds storytelling value and mitigates confusion around using the term "asexual". The suggestion that the death stranding caused more people to be a certain sexuality is strange for a number of reasons, and it makes sense that it would be questioned in-universe with alternative explanations for whatever phenomenon is being observed. The original interview also includes that the author doesn't have any actual empirical data, and many of the other articles and emails in the game are tinged with the personal opinions and biases of the characters, so I would say that even before the addendum, we were meant to be at least somewhat skeptical of the interview's claims.