Yahoo, Compuserve, AOL, Gateway Computers, Nokia, SEGA, Blockbuster, KMart, and countless more medium-large business that didn't have a strategy for the technology shift.
That's not the question was asked though. Sure, they were an industry leader in the 70s/80s but in the period 1990-2005? It's hard to claim they really were. It's one of the rare examples of a fallen giant getting back on their feet, most just slowly dissolve over a few decades. AT&T is the only other such example that comes to mind.
> AT&T is the only other such example that comes to mind.
If you're talking about the current AT&T, then I'd argue it's not a great example. The relationship between old AT&T and the company currently calling itself AT&T is tenuous. It would be more accurate to say the brand name survived, because it has good name recognition value.
Yahoo was more of a slow decline, and missed opportunities. They could have actually acquired Google and/or Facebook at one point, and could have been acquired by Microsoft at a later point.
The comment talks about "quickly changes the world around us rather fundamentally", "knocked off their perch", and "within a few years", which doesn't seem like an accurate description of what happened with Yahoo.