No one in here may like this opinion, but too bad. The answer is... Over-rated. Yes, his streak was fun, and made the crowd react very well. And, yes, I think they did a dumb thing with his streak, by one Pay-Per-view, have him destroy the Giant(AKA the Big Show), the next have him lose to Kevin Nash. Yet, he will always be over-rated. Let me explain.
He had a very tough time selling. I think he only did it once, and that was when Evolution did a number on him. Other then that he was just unstoppable. Which yes, that was his character. But his stiffness, and dangerous in the ring performance really ticked off a lot of performers. Jericho and The Rock were a couple of them. He couldn't throw a punch, unless he could actually hit you. We complain about Cena and his 5 moves of doom, Well Goldberg only had 4! Gorilla press slam, his flip leg submission hold, the spear, and jack-hammer. If you only have 4 moves, you have to have some good mic skills, which he didn't. Most of the time, it was him saying... "Your next!"
Crowd reaction was good, but so was the Warrior's, and he was over-rated by far. Not also that, but he only wrestled for maybe 6 years top. Yes I know the Rock had only 10, maybe even less, but people are still begging for the Rock's Return. Goldberg's little stunt at Wrestlemania XX still has people from the wrestling world upset. He messed up a lot in the ring, and as stated earlier very rough to work with.
This isn't all Goldberg's fault. I mean, he wasn't discovered at an Indy event, or a rival company. But he was known in the Atlanta area. He at times would hang out at the club with some of the WCW performers, and he was only 2nd or 3rd string on his team, so Bischoff offered him a job. I think he only had 3-6 weeks training before his match with Hugh Morris (Bill DeWalt is his real name), Bill did good at putting him over. Then boom, his rise to the top occurred less then a month. Then he had a US title reign, then Bischoff, in less then 8 months of him being in WCW he got a huge Televised main event, and got the belt. Everything happen so quickly for that guy.
If Goldberg stayed in the Mid-card area, for 2 years and won World War 3 instead of getting his title reign due to popular demand, I'm thinking he wouldn't of been so highly over-rated. He was fun to watch though, but over-rated indeed.