Clearly salvager is better, because its more flexible, for example you could trash a gold so that you can buy a platinum or colony. However 20+ places? That can't be right.
That's an artefact of the voting system used, I think, rather than of people's opinions. If everyone is voting Salvager as just slightly better than Remodel, it'll end up with a much higher average score, even if everyone's preference between the two is slight.
I don't think that's how the rating system works. You get that kind of phenomenon when you have something like a poll for which is better of two things where you vote for 1. Then the result can be 100%-0% if everyone prefers the same thing, even slightly. But here there's a ranking with linear scale, and 20+ cards landed between them. If everyone put them right next to each other, this wouldn't happen. People put a large gap, and I think it's justified.
Remodel is a little low, but Salvager is a lot better since:
1. There are just more situations where 1 expensive card is better than 2 slightly less expensive cards. Most notably, you can Salvage 5s to get Provinces, and you can Salvage Estates to get 5s.
2. It is much more rare that there's nothing at least acceptable to Salvage in a 5-card hand. A lot of kingdoms don't have a 2 that you want to Remodel Copper into, and you can't just trash it for nothing. And if you trash Silver, you lose buying power compared to simply not playing Remodel. At least Salvager gives +$1 there. Remodel is good (better than Salvager) for building engines with lots of cheap parts, and it's good in such engines, since the drawing helps find good targets, and the increase in total card cost maintains enough targets to keep Remodeling. But Salvager is also good in semi-engines and big money. It helps low-drawing strategies that need to end the game fast much more than remodel does. And this difference is bigger, at least imo, than the differnce between the two cards in larger draw engines.