>>12833133A couple of reasons led to him winning the world title at WM 20...
First, Brock quitting out of the blue to try to become a football player destroyed pretty much all of Vince's long term plans for the WWE as Brock was the future in Vince's eyes more than Cena was out of the OVW crop of rookies he inherited.
Vince had already put the one of the world title on Brock, which made him the youngest champion at that point. Vince got super cunty and decided to erase this achievement from the record books by declaring that Randy Orton was going to become champion ASAP and become the newest youngest world champion in the WWE.
Adding to this, Triple H's reign of terror had been catastrophic for the WWE and he had arranged for Orton to be put under his wing, partially to keep Orton under his thumb since Orton was always "plan b" if Lesner didn't work out.
Vince told Hunter was told he'd be dropping his vanity belt to Orton, which pissed Hunter off. He didn't think Orton was ready and shit talked him to Vince; which combined with how Orton was treated by HHH AFTER he won the belt from Benoit, being why Orton despises HHH even though Hunter has gone far and beyond to irrevocably link Orton in WWE lore as HHH's heir apparent with stuff like the Authority storyline.
Hunter eventually convinced Vince that he'd drop the belt to someone else who would be a transitional champion and drop the belt under the guise that HHH didn't want to turn face and that Orton's face turn needed building up. Benoit was insanely popular with the smark crowd and someone who was a HHH loyalist that would put Orton over and not try and hijack the storyline for his own ends.
Hence him winning and why Benoit never said much as Hunter immediately marginalized him for the length of his reign and why he never politicked against Orton to stay champion.