I'm guessing they are making an assumption that without Apple personal computers would never have take off and we would still be stuck in mainframe hell.

No: if Apple hadn't happened, personal computing would have flourished anyway. Intel might not have been so dominant in the µprocessor market, as the IBM PC was a panic response to Apple's success, and IBM's scientific PC, based on a Motorola 68K chip, might have taken a larger market share.

See Ted Nelson's book Computer Lib/Dream Machines for more on the state of personal computing prior to the start of Apple.