It is staggering how much HP has fallen from grace. I don't think a lot of people my age even know.
If you're a late millennial/early zoomer, you probably know IBM had a sort of "golden age" from the 1960s through the 1980s. You also know AT&T was a juggernaut (even if you can't imagine the scale of "Ma Bell").
HP though? Nobody my age knows how great HP was in the '90s unless they're either a retro computing nerd, or an EE who knows the Agilent/Keysight lore.
The timeline makes it all the more surprising. HP's glory days were the 1990s! A decade after AT&T and IBM were clearly declining! Somehow the recency doesn't play in HP's favor.
They torched their reputation so quickly and so thoroughly that I can't think of any comparisons. As far as I know, the only companies who did it faster were fraudsters, the Enrons and FTXes of the world.
That was basically entirely on Carly Fiorina, Mark Hurd and the board of directors. It's pretty similar to what happened to Boeing.
HP had engineers at the helm right up until Fiorina. She came in and destroyed a lot of what made it great to work at HP while not really doing a great job of managing the company.
Then Hurd came in and he just gutted the company to the delight of the shareholders. I came in right as Hurd went out as an intern. The place was in shambles when I got there. He'd fired and outsourced everything he could. The IT there was a complete joke. It was actually insane that HP decided to outsource IT operations.