When I was younger, traveling solo, I always got called off to the side and searched. I wondered the exact same things you are wondering in your writing here. I always travelled with a backpack and my brother, at one point, said, why not change your bag? (i.e. backpacks seem to be synonymous for younger female travelers as being drug mules -- and no, they don't travel with someone).
I didn't change my bag, but I noticed as I got older (a few more gray hairs) I don't get stopped anymore. So, I think it's more an age averse thing (icky patriarchy thoughts of women being married with children etc. etc.) Please feel free to throw up now 😜. And forgive me if I've offended anyone.
It's just that not all women want those things at the same time that other women might or even at all.
I say, go do your travelling, Ellen! Be safe and aware and live life to its fullest.