Most people find it extremely difficult to go against perceived majority opinion.
You can see one aspect of this for yourself by trying a simple social experiment: go somewhere a lot of people are partying and get at least ten to loudly and repeatedly urge another person to do something that's really stupid - about eight times out of ten they'll do it. In fact, if you're like most people, you'll have let some group con you into doing something obviously wrong or stupid at some point in your life and never afterward been able to really understand why you did it.
The reason is simple: mobs have emotional effects: it's kind of a regression to the monkey thing that also underlies much of the appeal of pro-sports - because the vast majority of fans are there far more for the emotional high they get from being part of a roaring crowd than for the event itself.
One major problem with being part of a mob, however, is that repetition leads to belief: most sports fans think they care about the sport. More tragically, in large parts of the world today you either hate who they tell you to hate, or they kill you - and when that goes on for a couple of generations you get children who not only truly believe they hate, but believe that hate to be justified by historical or religious fact.
Mob psychology is part of being human: part of the fundamental us against them thing that makes us what we are. Look back a few hundred years and you see scholars willing to accept the orthodoxy of the day prospering while those arguing the rather obvious reality that the earth orbits the local star were being burnt alive - and more recently Canada's leading enviro-fascist suggested global warming "deniers" should be jailed while numerous gorolites have demanded professional decertification and media silencing for weather professionals brave enough to doubt their nonsense in public.
Since mob appeal is basically just a human behavioral weakness it can, like most weaknesses, be exploited against you - and when the Wintel apologist community claims a 90% worldwide market share they're just making up a number in the justified expectation that a lot of weaker people will find this a compelling argument for joining their mob.
In reality, however, a million blondes can be wrong: majority belief can lead to decisions and actions with real consequences, but has no effect on whether those actions are right or wrong, smart or stupid - moral relativism to the contrary.
There's an IT bottom line to this: whether Wintel or Lintel makes more sense for some organization isn't up for majority vote - it's a horses for courses situation with a mob on one side and reason on the other, in which the decision maker has to look honestly and carefully at the factors going into his choices.