It's not quite ignorance is bliss, as I consider myself quite knowledgeable on PC internals (I built my first Pentium 2 machine back in the 90s, used a pencil on my AMDs until the AXIA-Y came out, overclocked TBirds, Semprons, etc., balancing the voltage and clocks) but there came a point where I simply didn't want to have to open my PC a few times a week. Coupled with the fact my job went from managing 200 desktops to managing ultra-stable servers, I just found the Mac was a simpler solution that didn't demand TLC to get on with the job at hand. Coupled with the constant expenditure for the latest and greatest, the "building your own is cheaper" fallacy became apparent after a while.
I switched to console gaming around the same time when I realised getting the OCed rig to perform 2fps more was the game I was playing, and not the actual game. When you load 3dmark more than Grand Prix Legends (or UT, Q4, etc) then you know it's time to change the paradigm.
Also, you don't hear about many Windows laptop users complaining about the lack of ability to overclock their CPU or swap out the GPU, do you.
Like I say, chopping PCs was a phase. I hope many people out there still enjoy it, but I feel I've outgrown it.