Brainbox They didn’t go so much with ratios, as the WBC rules said (about 20 years ago) espresso was made with 14g of coffee and to the line in a standard shot glass, including crema. Which I thought was pretty stupid as crema was a variable and how long after the shot was it measured. The rules were essentially meaningless.
That said, a 2:1 ratio was really where it was going.
Obviously most of the influencers were still in Nappies, or shorts in those days.