It's in the ears of the beholder
I'm probably a little older than Alistair Dabbs as I went to university in the late 70's. The average student then generally had a crappy mono 'record player' , or more accurately record destroyer, whilst only the more fussy/rich had a set up usually based around components from Wharfedale, Garrard and that other colossus of the cheap British 'HiFi' Clive Sinclair. At home My parents had a 'radiogram' where the quality of the wood veneer was far more important than the sound. So most people put up with sound quality far worse than today's MP3 players. I think that the average, admittedly not Hi Fi, sound quality of music that people listen to is much higher than it was 30 or 40 years ago and for most people that is good enough as it always has been. There will also always be people for whom this isn't good enough, myself included although i wouldn't go as far as:
Context is also important. If I really want to listen to music i will always prefer the source whether it's Vinyl or CD, I have never messed around much with FLAC etc, but when i am enjoying an evening around the dinner table with some of my amazingly witty and intelligent friends then MP3 is fine, plus I don't have to keep changing things. The same for listening in the car.
So chacun à son goût as Nigel Farage would say. He likes a pint or two, apparently.