Alba works out extensively. She has a strict diet.
Mischa barton admits to never working out.
But you're right, they are expected to be perfect.
Most of these women "stars" today can't hold a candle to women like Rita Hayworth, Elizabeth Taylor, Sophia Loren, Marilyn Monroe, and so many others of days gone by. They are so outclassed on all fronts by the female stars and celebrities of yesteryear it isn't funny. Catherine Zeta-Jones is one of the few who comes close to the standard we used to have for female movie stars and celebrities.
Most of the women pictured are slender and physically fit, but have no figure to speak of. Most are sort of boyish looking.