It's also probably the best word to convey what is happening to a general audience.
That's circular logic because dictionaries keep changing their definition to match what ignorant people use.
https://www.etymonline.com/word/epidemic -- "epi-dēmos", "among the people".
If you hold close what the term says, and regard the use as a derivation, you develop an aware, rooted terminology.
But then, you'd lose the grounds to embrace a conventional derivation as what the term means - which is what you just condemned.
That is indeed how this "language" thing works.
Was this intentional? You just made the same error.
Have you not heard about the "obesity epidemic"?
Also, pandemic is not normally used in non medical context while epidemics is frequently used that way and was for years. The journalist probably decided to use the common words in their common meaning instead of going for obscure usages.
You have no idea how language works and provided a weak example that didn't make any sense.