At the time, I thought Shirley Manson was very cool. However, I think the main problem with Garbage was that they were always one of those bands that seemed more like a corporation than a gang. Which is not cool at all.
However, having dismissed them as a throwaway mistake of my youth, I found myself listening to some of their old songs. And, amazingly, they hold up. There are some good pop songs mixed in there. (There is also some crap, but the 90s were a funny old decade.)
Their first two albums are pretty good. Even the third has a couple of decent moments. I wouldn't know about anything beyond that, as I have never heard any of it. (How many albums did they actually make?)
Anyway, Garbage weren't totally shit. Nobody was more surprised than I.