Spinning at 140+ RPM is an advanced cycling skill, and one that is entirely unimportant for the majority of riders.
This is where we disagree. This is not hard stuff to learn without training of any kind. Just ride for 12 months and you should easily be spinning that.
And again, you keep arguing that "not everyone wants to be as advanced" which is true. Care to explain exactly why then it would make sense for a less advanced cyclist to use heavier more advanced track gearing like 46x15?