My point is simply to demonstrate that the things we thought were great 20 years ago, we tend to feel differently about now. 20 years ago I definitely thought USB A was great. Today I don’t think it’s anywhere near as good as USB C, and I expect in 20 years time I’ll have a different perspective again. But the innovation that got us to here will clearly be hampered by legislating standards into law, for the reasons I explained above. So perhaps not. Perhaps in 20 years will all still be using USB C connectors, living in complete ignorance of what innovations we forewent in order to legislatively solve a problem that barely existed in the first place.
But your example is trying to prove a negative. "How many innovations are stifled by regulating this connector?" Unknown. Try this: how much e-waste is created by not having a standard connector? Also: will you trade your children living knee-deep in a toxic sludgepile so that we can continually keep innovating? Maybe new iterations of connectors making entire devices obsolete every 'less than 20 years' isn't the great outcome you think it is.