For me, it's all about fashion. Maybe bibs work for skinny people or overweight people and people who spend a lot of money on bike clothes and feel free to indulge in confirmation bias.

I have an average build, I'm not overweight or skinny, my bike shorts don't fall down, nor do they dig into my waist, and they are as comfortable as my bibs (I have a small collection of bibs and shorts).

For bibs, I agree with a poster above, full zip jerseys help with bibs.