We get that wrestling fans don't demand gritty realism from their sport -- they're not stupid, they understand the concept of suspension of disbelief. But regardless of how ridiculous the storylines can get, at the very least they have to make it somewhat plausible that the guy who wins the match could actually have done it. You know, because both guys in the ring are professional wrestlers and it's not, say, a muscle-bound superman versus a pudgy middle-aged desk jockey.
There was actually a storyline behind this (because if Leno just showed up and started whaling on Hulk out of nowhere, that wouldn't have made any sense). Basically, Hulk Hogan was a heel (bad guy) at the time, and his manager was Eric Bischoff, the real-life president of WCW and most likely the guy you can blame for all of this bullshit. Bischoff's character randomly decided he wanted to be a talk-show host and launched the excruciating Nightcap, 30 minutes of intentionally awful jokes smack dab in the middle of WCW television. Every fucking week.
The torture only stopped when Jay Leno voiced his fake concern and challenged Hogan and Bischoff to a fight, because wrestling. There are lots of ways they could have resolved this without pretending Leno could actually wrestle anyone for five minutes without coughing up a lung, such as having him manage a real wrestler (like the WWE did with Donald Trump), but no, they instead set up a tag-team match. Leno went and found himself an actual wrestler for a partner, and the match was on.
Via Wrestling Legends Forum
For the first time in his life, Hogan realizes he has chosen a ridiculous line of work.