Yeah, after Vince broke his thumb against the Steelers he was never the same. Quickly faded with the Rams, struggled with the Bills and then couldn't even catch on with the Packers.
With Vince, his legend is in getting the Rams to the SB for the first time ever. Goff getting them to their 4th SB isn't going to compare. As mentioned, Vince's miraculous pass to Waddy to beat the long hated Cowboys was epic. Goff's Rams beat the Cowboys too but it was CJ Anderson that was the star that day. The Saints game wasn't a particularly memorable game for Goff as much as it was a controversial PI call that gave the Rams life.
Then there's the SB itself. The memories of Goff are of missed opportunities and coming up short. With Vince, it's of David vs. Goliath. Going toe-to-toe and having a lead in the 3rd quarter against the dynastic Steelers made Rams fans proud.
Ultimately, I think Vince was revered more because he was jerked around by the Rams and there is more a feeling of what could have been? What if the Rams had kept him? What if he hadn't injured his hand? With Goff, his memory is too tied to disappointments. Wasn't a clear choice when picked. The cost to draft him. Terrible rookie year. SB collapse. Two years of frustrating play. The shocking departure. It all adds up to negative memories.
When Vince fell off, it coincided with ED's emergence so it seemed less critical somehow. When Gurley faded, it was Goff's time to take over but instead, that's when he began to struggle. Vince is just associated with fond memories and Goff is mostly disappointment.