Upon further reflection, I can't help but think of Windows 95 and the world wide web (with the Pentium and ATX standards developing on the hardware side) as being the turning point between the previous and current "overall styles" of computing.
Before, PC was a minority niche with a steeper learning curve, and everything having to be done manually starting from the DOS prompt. After, it was a whole new world - GUI based, connected to the world, designed for average people to use, a greater % spend on the marketing and prettification sides, and variations on Moore's Law accelerating hardware evolution almost beyond recognition.
This is partly an acknowledgement that PC eras may not be truly defined by hardware era alone, because other concurrent factors played equivalent parts too. Intel and Microsoft, among others, spent a LOT of time and effort working together to craft 'the next gen computing experience', and doubtless still do.
Supporter of PicoGUS, PicoMEM, mt32-pi, WavetablePi, Throttle Blaster, Voltage Blaster, GBS-Control, GP2040-CE, RetroNAS.