I somehow doubt Microsoft are skilled enough to execute such a dastardly plan. It's probably more just poor luck and poor QA that has left us all stranded (I'm in the same boat as you - cheap upgrade - now no luck upgrading to 8.1 after 4 attempts).
Luckily... I'm writing this on my imac that updated beautifully to osx mavericks today without a hitch. If Win 8 hadn't forced me to buy a mac I'd be really pissed at the **** upgrade to 8.1 fiasco.
MS will eventually figure it out but until they do they'll keep people guessing and let them try to install to no avail.