Then I'd suggest you reduce the weight until you find something you're comfortable with, and slowly build up from there. You don't need to use the same weight for every single exercise.
To build general strength in your thighs, it's best not to do repetitive motions as well but to hold certain positions longer and longer.
Look up the Warrior 1 yoga pose for example, it's basically a low lunge with your arms raised straight up. Do that as a warm-up (hold for 5, 8, 10 seconds increasingly) and build up your thigh muscles.
I have cables that are 15 years old and still work. Not USB-C obviously, but A-A and A-B, but also some USB-C cables that are close to 10 years old now and came bundled with some OnePlus phone (the 3 I think?).
The key to not breaking cables is to not roll them up tightly. If you need to transport them, put them very loosely into a bag or something, and everything should be fine.
I'm using the cheapest 2m long cables I could find online, they don't fail if treated correctly.