Maybe they're all just passing on the hate?
Seriously though, the short waistcoat/low rise trouser/belt combination is pretty prevalent these days, you're right. I don't like it either. But at least it's a more deliberate choice to viewers (being in line with modern trends) than a loose waistcoat. That has the function of making it more acceptable to others today, even if it will date much more harshly than a loose waistcoat over time. Simple solution: just get a waistcoat that fits reasonably correctly.
No, I'm pretty sure i was the only one hating. To me it just looks like a bar slut in a tank top showing midriff.
That bit of mental imagery is going to stick with me a long time...