I mostly agree with him personally. Although I think a worse aspect than booing is the expletive-filled outbursts (along the lines of "You're f****** s*** Travis/Lowe/Pedersen/insert scapegoat of the era!") and the enraged snarling at missed passes/shots.
You could write a dissertation on the psychology of modern fans and why a far greater percentage are customers/critics as opposed to supporters/fanatics, than was the case in the past. My chief suspect is the money that got pumped into the game in the early 90s started driving a wedge between fans and players. Its harder to see you all as one big family, in this together etc when 10,000 of the family get paid £25k per year, and 20 of the family £750k per year.
The thing about the money aspect though is it doesn't change anything else. These are still young men, still humans, with the same variable confidence and the same psychological reaction to praise and criticism as everyone else. Booing/criticising/abusing your own players makes them play worse, that's a guaranteed fact. Why fans would want to waste their own money by helping their team lose is beyond me and completely the opposite to my attitude at games.