Changed the (IT) world
I recall the days around the adoption of SubLogic's Flight Simulator by MSFT, and more importantly by IT (then often called MIS, if not DP) departments.
IBM's failure to prevent "clones" originally promised "A thousand flowers" of PC innovation, but it soon became clear that much PC software bypassed the OS to bang directly on the hardware. The funkiness of early drivers may have had something to do with this. Purchasing departments started evaluating the "quality" of prospective vendors by running, you guessed it, Flight Simulator. Although companies claimed that they were buying PCs for word-processing and spreadsheets, ability to run Flight Simulator became the Gold Standard for "IBM PC Compatibility".
This meant that trying to compete on features like CPU speed, power-supply reliability, or graphics was pointless. The only real criteria were "bit for bit and bug for bug" behavior, and of course price. This drove "white box" clone prices through the floor, while simultaneously reducing the need for shrink-wrap software developers to produce various versions of the products. One (later two) floppy disk format, a handful of glitch-compatible video cards, and we're done. Truly a Golden Age.
Yes, I remember Turbo Buttons, and how infrequently they were used (or, presumably, tested).
But imagine a world where PCs could compete on something other than price, and software developers could code to a published standard with confidence that a rising tide of PC performance would lift at least a few boats.