ZigBee is gaining popularity over Z-wave these past few years (there's more and more brands like Philips Hue or Belkin implementing ZigBee in their devices) but there's still no standard.
There are pros and cons for each protocol and no one can tell you to choose one or the other. ZigBee is gaining popularity over Z-wave these past few years (there's more and more brands like Philips Hue or Belkin implementing ZigBee in their devices) but there's still no standard. Matter is trying to deliver a unified protocol for connected things but it takes time.