Makes no sense. Plenty of folks live in Manhattan.

They're probably mainly thinking about Midtown East, which is almost purely an office hub and indeed pretty empty on weekends. It's kinda nice being there and feeling eerily alone.

It used to be FiDi was the same, but it's become pretty residential. Still, I know many restaurants there that only open M-F, especially on the eastern side where fewer tourists venture.

Everywhere else in Manhattan is sufficiently residential enough (or in the case of Midtown, touristy enough) to be lively on nights and weekends.