I don't think that's it even makes sense to compare the two, and not even from a gameplay perspective but very much on a narrative level too. Witcher was an epic fantasy tale with a very operatic style, while Cyberpunk is more like a techno-thriller mixed with some noir, so it's just a completely different kind of story.
But whatever, if you really wanna argue which game was more successful at what it tried to be, I'd say that TW3 easily wins here. Its storyline is thoroughly engaging, it has great writing and characterization, and lots and lots of memorable moments, including some truly grandiose battles where every major character that you've met along the way and care about participates, which raises the stakes every time and makes for some epic fucking set pieces.
Cyberpunk, on the other hand, was only decent. It's certainly engaging to some degree as a techno-thriller/noir type of story but I can't say that it was like super impressive or anything. The concept itself is interesting, there are some neat quests here and there, but overall the execution of it all was a bit lacking. The pacing as a bit all over the place and some cutscenes have very strange and downright janky editing so they're not even half as impressive as they should be. I didn't feel as engaged in the story or characters as I was with other works in this genre either. The most I ever felt engaged in this game's story was when I was about to bang Panam, lol. But other than that, I didn't even like any of the characters all that much. The relationship between Silverhand and V didn't feel all that convincing and a lot of it I think has to do with a very one-note delivery from Keanu Reeves where he tried way too hard to sound badass. Sorry Keanu fans, but most Hollywood stars simply aren't cut out for this kind of thing. In most cases it's down to the fact that they don't do this type of acting very often so they're not used to doing voice over work and the result often feels very awkward and unnatural. With Judy I just thought that she was a brat and an idiot. The Japanese bodyguard dude whose name I can't even remember now was just plain boring and I accidentally let him die without even realizing it, lol. I don't really remember that much about River, or whatever his name was. The best character in the entire game hands down was Jackie because he had the most personality, charisma, motivation, and it actually was kinda sad when he died. And that's the roster of allies that I'm supposed care about throughout the game? Gimme a break, none of them have shit on Ciri, Triss, Yen, Lambert, Eskel, Vesemir, Zoltan, Dandelion, and many, many other cool characters from The Witcher 3.
Also, where the fuck are Cyberpunk's villains? They're so damn weak and not developed AT ALL. Even the cool cyborg dude can't save the show simply because he's barely in the game at all, and there are like zero confrontations or even backstory provided about him before you square off towards the end of the story. And by that time you're so overpowered that the bad guy bites the dust in seconds anyway. It's so anticlimactic.
So yeah, sorry OP but Cyberpunk is an inferior game on almost every level except the visuals.