It comes down to if you want to go practical (Apple Watch) or entertaining (PS4 Pro)
I own both a PS4 Pro and an Apple Watch, and I would go with the Apple Watch. While I love my PS4 pro when I use it, I use my Apple Watch daily. The upgrades the pro has over an OG PS4 are awesome and quite noticeable, but if you've made it this far with an OG PS4 and are okay with it I'd go with the watch. Now if you were planning on getting a 4K HDR television soon then it'd be a different story.