The real lesson is that once a technology looses, the people who invested in the looser will run around forever calling the looser better.
In the case of VHS vs Betamax, VHS won because it was better overall. Some people point to one or two advantages of the Betamax format, but ignore that overall it wasn't better than VHS. (Because Beta tapes were physically smaller, you were usually forced to use a slower tape speed, loosing the very minor picture quality improvement at the highest tape speed. Thus, longer prerecorded Beta movies looked worse then their VHS versions.)
The same thing is also the case with git versus Hg. I used Hg years ago because it was easier to learn; but once I learned git, I see no reason to go back to Hg. Yes, Hg has an easier learning curve, but that's one particular detail.