Meta: As plenty of commenters have pointed out, this kind of statements (and similar ones like "PV electricity is the cheapest one", etc...) are entirely true _with some attached caveats_.

For example, an EV is both undoubtably cheaper to operate than a gas powered car ; and infinitely more expensive to operate if you can't afford to buy one in the first place.

Similarly, the price of kWh of PV-generated electricity is both lower than pretty much everything else as this point ; and, basically infinite when the sun is down and your 4h battery has run out.

Is there a proper math concept to fairly express those things ? "Mean", "Average" or "Median" fall short. Mean with very very large error bars ? "Average with substitution" ?

In the end, I can't wait for all those circumvoltions to be irrelevant (when EVs are just cheap to buy too, and electricity has enough storage to bake it into the price, etc...)