How old is too old for a woman to have her bra straps showing?

I’m in my 40s, and when I was growing up it would have been unthinkable to wear something that allowed your bra straps (or underwear, for that matter) to hang out. I’ve noticed that for most younger women, this is no longer a big deal. They wear what they like, regardless of whether or not it covers their undergarments. See here for an example. NOTE: My bras are not red. They are boring, plain colors. I’m wondering if it would be inappropriate for someone my age to follow suit.

The youngsters usually have the benefit of slim little straps, while mine are about half an inch wide. It takes a lot of work to hold these babies up! While less attractive, they are also harder to hide under a tank top or similar clothing.

On the one hand, it would be awfully freeing to be able to wear a tank without a shirt or cardigan over it. On the other, I don’t know if I’ve got the guts to do it. Or if I should, anyway. Your thoughts?