In the shows referenced, the participants always return to the 21st century after a period of time.
I am a huge fan of time travel novels. I happen to know one writer of such, and next time I see her I'll have to ask her some questions about this.
Okay, so you go back even 100 years, and you know you will be without the modern technology of cell phones and the internet. But even that long ago, what is coyly called feminine hygiene products would have been quite different. Kotex, which made sanitary pads for women's menstrual periods, came about around 1920, although a quick internet search indicates that similar products came into existence around 1900. But much earlier? Rags that had to be washed. And no very good way to use them, meaning you'd have to cram some inside your underpants, and the blood would soon leak through, depending on how heavy a flow you had. I know, too much information, especially for the guys reading this. But the reality of such things matters. I am sure that among the reasons men got to dominate women so thoroughly is connected to the inconvenience of our monthly cycles.
Perhaps this is a bit odd. but these are the kinds of thoughts that are always lurking not far below the surface for me. It's almost as if I've recently arrived from sometime in the past and so I always notice modern conveniences.