“Fanboi” is a fairly common insult used by non- / anti-Mac users against those whom they perceive as having blind devotion to the Mac.
Yes, fanboyism exists for Macs, just as it does for many other products/pastimes/theories.
However, in a class of Mac users (namely, those who have been using Macs since at least the 90s) there is a sensible and defensible reason for why — if it exists — it does so. (Although, that said, in my experience the longer someone has been using Macs, the stronger the attachment but the less preachy the approach.)
If you were to go back in time to the late 80s and early 90s, there was a real sense of “us and them” for Mac and PC users. The two machines were poles apart. Most people used PCs. Most office work (other than graphics and publishing) and most games ran on DOS/Windows. Those who used Macs were generally quite conscious of fact that they were a minority. Often, a minority that was discriminated against: for every brilliant Mac-only program, there were others — often programs people were required to use to interact with work or governmental systems — that were PC only. (And other Mac only programs were often ported to PC, with the Mac side then being left to languish or, worse, killed; Adobe (FrameMaker), I’m looking nastily at you.)
Most Mac users had seen the clunkiness and shortcomings of DOS and early versions of Windows (say 3.0) and they preferred the Mac way of doing things.
These same users watched as Apple went from making such superb machines as the IIci and the PowerBook 100 / 140 / 170 to a series of clunkier and crappier machines such as the Performa xyzzy alphabet soup lineup, the unreliable PowerBook 5xxx series, the Mac IIvi and the Mac IIvx. Whilst a few machines stood out among the dross (eg the superb Quadra 700 and 840av, the 7300 and the Blue and White G3), the overall trend was down (in quality and performance) and up (in price).
Apprehension among such users (in which I count myself) rose sharply from about 1995 (when Windows 95 demonstrated that Microsoft was finally starting to learn how to make a semi-stable and semi-usable OS) and peaked in about 2000, when Windows 2000 arrived (mostly stable and mostly usable) — during which period Apple had almost drowned in the morass of Taligent / Copland / Pink, and its truly revolutionary Newton first languished and then had its lunch eaten by the Palm Pilot.
There was a real feeling that — even after the return of Steve Jobs — one might be witnessing the death of Apple. (Michael Dell’s advice in 1997 was not at all unsound on a purely business level.) That carried with it the realisation that one might have to be forced to the PC going forward.
To those who hated the crappiness of DOS and early versions of Windows, that was a really dismal thought. Those who had had to fight the dross available in the PC world, and who had finally set up a Better Way of doing things using a Mac, did not relish losing their hold on a different way of computing, where the OS got in your way far less, and you could use your computer to do the task you wanted to complete, rather than using a computer to be able to use a computer.
A natural reaction to that fear was to talk up the Mac and Apple; support the sinking ship in the hope that you might help bail it out. While it would not have worked any more than, say, Delorean car owners could have propped up their company — it was the iPod that saved Apple — it was an eminently understandable reaction. Traces of it do still linger in Mac veterans, although (as set out above) my own experience is that most fanboyism today belongs in the category of “none so religious as the newly-converted”.
1. Fanboyism is a common phenomenon in sports, cars, beverages etc etc
1. I know; FrameMaker started as a SunOS program. But its next port was to the Mac and later ports were to Unix systems including NextStep; for those using desktop computers, the only supported platform was therefore the Mac.