WCW, hands down.
And that's not even counting Arquette's run.
Looking back, Goldberg's reign was the last time that belt had any value and that's because Goldberg's legitimacy warranted the title. They kept putting it back on people that didn't need it, except for DDP. He deserved a reign but gotdamn, 3 title reigns and cumulatively, barely 2 weeks. Which is the main problem with WCW's title.
They switched it too often. There was a period in '99 where they had 7 different title reigns in less than 100 days. Hell, in May of 2000, you had 7 different title reigns, as well as a vacancy. When the belt is passed around like that, amongst people who don't need it, it loses value.
Sure, WWE's belt changed hands a lot but when it did, at least it furthered a story you were invested. When WCW did, it was to further a story that should've never been a story in the first place, such as Sting turning heel. In what fucking planet would Sting turning heel on Hogan in '99 actually work? And why the fuck did Hogan have the belt in the first place? If anybody should've been in that position, it should've been Goldberg who, IMO, was the only guy in the company that could make Sting heel. But, I digress.
Changed the belt too many times, for no reason. Didn't use it to create and reward deserving talents, post-Goldberg. And tended to put it on everybody that didn't need it. No fucking way Ric Flair should be a World Champion in 2000, let alone winning the belt because somebody handed it to him. And why the fuck would Nash give him the belt? I don't know and neither did Russo but he did the shit, anyway, along with a bunch of other fuckery that year, regarding the World Title.