Form fitted is not the same as tight.
I don't go to gyms anymore and I never got into weight training or equipment. You've got all the weight you need in your own body, as far as I'm concerned.
The restriction of movement I was speaking of probably won't be noticed when pumping iron, that's true. But it will doing yoga, primal movements, stretching, cheer workouts, etc. Hence the popularity of highly stretchy, form fitting workout clothing for women.
Other positives of note: form fitting clothing has no gaps so you don't have to worry about exposure. They simply feel good, as evidenced by the fact that even people who clearly never exercise have taken to wearing them. Women's bodies are notoriously varied, ergo the way it molds to you and the stretchiness of the fabric covers those irritating fit discrepancies in most women's clothing a great deal.
Regardless, it shouldn't matter and it doesn't. No matter what you wear or how you wear it, as a woman some man is going to make an issue of it and let you know his feelings because for some strange reason men cannot stop scrutinizing women's every decision and commenting on it. It's a form of pecking.