> And unfortunately from a user's standpoint, a redesign is one of the worst things that could happen to a site. Because however cramped and difficult a site might be, there are people who use them daily, and changing the structure completely overnight would abandon the most loyal users. That's why it's easy for startups to come up with nice sites in 2010, they haven't had a website since 1995 so they don't have the baggage of previous users.
So we should never redesign and make a website more functional because old users might not use it?
I know you're asking that question to point out what you consider to be obvious, but actually I would say the answer to the question is more "yes" than "no".
A redesign in this case may help get new users, but it's much easier (and more cost-effective) to retain existing customers than to gain new customers. So, if your change upsets existing users on any meaningful scale, then it's probably not a good idea.
I'm not saying to never redesign. I'm saying that you should redesign iteratively and in small steps, so that both existing and new users benefit. You never want to attempt gaining new users at the expense of existing users.
So we should never redesign and make a website more functional because old users might not use it?