Yeah, you point out the winners, think back 15 years ago. How many competitors were there just in the realm of word processing? Every format but the eventual winner (which couldn't be determined at the time) is now completely useless, whereas an abundance of old dud open image formats can still be opened (which is nice because some are really easy to programmatically generate)
I don't think that's true. I can still open WordPerfect docs from 15 years ago, with less faff than it takes for, say, VRML (which was an open standard).