I was in a tiny bar in Seoul a few years ago where the bar tender was also the DJ. This guy would go from making drinks to picking up a pair of headphones and cuing up the next track, pulling vinyl from a shelf. One of the coolest things I’ve seen.
It depends on the age of the DJ's career. There's a lot of ego involved with being a DJ, and using sync is seen as somehow "lesser"
because it takes no skill to hit sync, or even just visually match bpm numbers and the beat on the screen. Nevermind that there's a ton more to being a good DJ, for people that grew up with vinyl, the loss of the need to beat match by ear means you can become a DJ without having that particular skill. So older DJs with more established careers judge the younger newcomers for not having that skill, but for DJs that have only ever used digital and have never had to carry a milk crate of records around, they've never not had the sync button. And they don't feel any shame when using it.
You can use sync, but I don't think it's that widespread.