Companies change focus but hang on to their brands for consumer recognition, despite radically different strategies. The "HP" of back then is the "Agilent" of today. Similarly, yesterday's "Motorola" is today's "Freescale".
Back to the point in hand, Apple have somehow managed to make themselves de-facto for musicians, video editors and people that draw pretty pictures in Photoshop. These are the 'halo' users and mere mortals that think of themselves as possibly being creative one day buy Apple in part because that is what the creative professionals use. The fact they get no further than 'Crazy Birds' on their iPad Air is neither here or there.
HP should have worked on a similar strategy but in the 'technicial/scientific' sphere rather than the 'creative' sphere. They should have listened to and looked after the customer base they had built up from selling things like 'scopes so that the de-facto kit to buy for anyone doing anything vaguely technical was HP. This too could have had a halo effect, so anyone studying something like engineering would instinctively want to buy HP rather than some other cheap Chinese junk.
I keep hearing this sentiment bandied around but I have seen no evidence of it in real life. Most of the "mere mortals" I know that use macs don't make any pretensions beyond "its much nicer and I can afford it." Nobody is saying to me "I bought it because I fantasise that one day I'll run a recording studio from it." And who on earth buys iPhones and iPads to be "creative?" What a load of nonsense.
Now, on my Mac, I do exactly zero multimedia related things. So I agree that the multimedia thing isn't necessarily true, but that's what I hear about Macs from not-technicals.
BTW, as long as it can run X, compile Python from source and run Emacs, I'm perfectly fine.