You are right, they are only really useful for charging (though 240w - beasts) or keyboards. I’ve given up on trying to find silicone cables for data transfer and just buy thunderbolt which are typically rubber (Apple ones are braided these days, but it’s a very tight braid).
I ran through their website and all the ones I selected were USB 2.0, and there isn't a filter for speed as far as I could see.
So no, it appears that "chubby cables" aren't the best.
You are right, they are only really useful for charging (though 240w - beasts) or keyboards. I’ve given up on trying to find silicone cables for data transfer and just buy thunderbolt which are typically rubber (Apple ones are braided these days, but it’s a very tight braid).