I honestly don't have the slightest clue how yahoo stays in business. And I don't mean that as rhetoric, either. Other than Bloomberg I don't get where the money comes from. I hope it's not organized crime...
I'd probably read a biography of the company out of curiosity.
All I can do is guess, but if you go to their home page take a look at the sidebar. That's a pretty impressive range of services. You can manage your email, buy stuff, check the news, see what's on TV, check the weather. It's AOL but on the web and for non-technical people having one place where you can do everything is probably pretty attractive. Especially if it came set as their web browser home page and they don't know how to change it or create bookmarks.
That's not a long term sustainable business though, as the non-tech savvy oldsters in the population get replaced by youngsters that mainly use mobile devices and apps anyway. I think Cringeley has a point. Yahoo should slim down and use it's remaining financial weight to turn itself into a tech industry specialised version of Berkshire Hathaway. Copy Google's corporate structure and hive off the portal into a subsidiary of a holding company that focuses on managing investments.
I think they should do the opposite. Even as a young guy their product is very valuable, or was, but they're destroying it piecemeal, closing the unprofitable services and not realizing that the value came from having all those services in one place.
They need to massively cut costs and write down a lot of their value. Their portal with all their services could easily be a cashflow-positive sustainable business. But because they were once big they're not willing to do what it takes to be sustainable now that they're small; instead they're selling off all the good bits to fund wasteful moonshots.
I'd probably read a biography of the company out of curiosity.