So let me tell you young'uns back when 1e was changing to 2e.
There was no confusion
At worst there was a quick conversation on which ruleset was being used (or some sort of hybrid). If you bought and/or showed up with the wrong PHB, well, someone let you use theirs. It was not human sacrifice, dogs and cats living together, mass hysteria. There was, at most, a couple of seconds where the wrinkles were smoothed out, and then the game started.
And this was with an edition shift with more changes than what we're getting this year (although they did have enough compatability to be played together) and at a time when communication on what was happening was far harder to come by.
Face it, the vast majority of people aren't going to be confused by this, and those that are, the vast majority will have their confusion cleared up quickly. As for those who accidentally bought the wrong product, well, the vast majority of retailers have return and exchange policies for this exact situation. Attempting to steer this discussion by "lamenting" the theoretical and unlikely fate of the 0.1% of the 0.1% is, at best, disingenuous...