Nobody has to do barbell training. It's kind of a short cut, nothing more.
There are plenty of people in the gym to observe. The girls on the treadmills are skinny like how most girls want to be. The girls on the weights have more definition or else they are fat or body-built. The girls who never pick up a barbell but do either machines and chinups have more defined muscles than I do, but maybe that is only because they are thin enough to do chinups.
I can't tell another woman what is best because I don't think there is a best. I like barbells because of the reward of making progress and because it's a shortcut to strength, but they do not make a fat girl slim and they certainly are not the only way to get strong or healthy.
Female, 5'3", 48, Starting weight: 163lbs. Current weight: 135.
Starting bench press: 30lbs. Current bench press: 75lbs.