Zucker is a 20-20 middle-6 winger that brings speed and physicality, he has just completely lost his hands and goal scoring touch from when he was younger. He's generating a ton of chances himself, he's just not producing whatsoever:
He's a $3.5 million player that is paid $5.5 million. He's not a bad player whatsoever, and trying to paint him as that is objectively false.
He has actually aged in a similar manner to another former Penguins player, Chris Kunitz. In about 2015 or 2016, Kunitz seemingly lost his hands completely and went from a consistent 60+ point guy to a 40 point guy at best. His hands were completely shot and he slowed down a bit, but he was still causing havoc with his physicality and was still a pretty useful player for about 4 years after he started falling off. The big difference is that this happened to Kunitz when he was 35 while Zucker had this happen when he was 29, so there is a huge age difference there, but Zucker is and will still be an effective player for the next few years at minimum. He's just not worth what he's paid anymore, which is why his value is effectively nothing right now.