The article is ill-informed garbage, really bad

As far as favored female body types are concerned, Twiggy and the associated youthquake were simply a freedom alternative against the cinch-waisted full-figured full-skirted Dior postwar post-austerity babe JUST AS (DEJAS VUS ALLOVER AGAIN) 1920's 'flapper' was a freedom alternative post WWI with 'boyish' waist-free figures (including many bound large breasts if they had them) creating an extreme alternative to corseted hourglass figures, all topped with radically cropped hair (gasp! especially shocking! females did not cut their hair! they spent hours a day caring for it!)

1920's flappers in turn were DEJAS VUS ALLOVER AGAIN of the new radical slyph-like female body silouhette of the Napoleonic era with tiny breasts above the new 'empire' waistline, discarding the pre-revolution hourglass corsets and huge powdered wigs and heavy silks for very thin fabrics (sometimes wettened to reveal the bud-like bodies even more) with cap sleeves revealing arms and simple hairstyles.

The actual heavy muscular and fatty Rubensian ideal was only a western favorite female type for less than a century and never came back (tho monks may have preferred farm girls that way for a longer time period, they were not preferred women of class.) As for before the Baroque period, you have to go a millennia back and to other cultures. That female body type is not favored in western Renaissance, Mannerist or Medieval periods, that's for sure