Maybe referring to this article which i found linked on a non long hair site : yahoo.com/lifestyle/hairdressers-bob-cut-blow-drys-coronavirus-162404247.html

It seems to be mainly about eliminating salon blow dries.

They then suggest bob cuts as quick and practical though I don't see how a blunt trim of long hair would be any slower. It seems like an obvious ploy to increase salon business which is understandable.