Smex swings can be crochet but not with yarn has to be sturdy with the swinging the body will be doing.

Rope strength is determined by the material and number of plies (individual strands) a stronger fiber with more strands can also be flexible. This also applies to the fiber used for yarn. So thin but flexible rope could be used to crochet with a large enough hook (it's the act of making the stitches).

You could crochet rope/string. You could make a thing suitable to hold you from that material. Normal wool/acrylic yarn would be too soft and stretchy. You can crochet with anything string like. You would need a modified hook/to use hands to do so with proper rope. That would work.

Ok. So, crochet is the technique. If you're using a single stand yarn, yeah you're limited to the tensil strength of the fibers (which can be ANYTHING - wool, cotton, rayon, silk, etc.) within that bulk determined by that yarn council. HOWEVER, if I were to crochet something for weight bearing, I'd likely not use a craft yarn and look for a nylon or something similar and likely braid some nylon ropes together to increase their overall strength.

I’ve crocheted with wire, it’s the technique, not the material that makes it crochet

Whether it would work or not, it'd be pretty unsanitary - nothing about that project was saying "easy to clean" and we KNOW what Rose's main kink was...

Crochet is a technique of fiber arts. You could crochet a lot of different fibers.