I mean, you can’t exactly just throw computing power at modern cryptography and expect to get results. I don’t know the exact numbers off the top of my head, but I believe all the computing power on Earth right now would take on the order of at least thousands of years to brute force a good password hash (assuming a strong password), and that’s assuming the attacker already has the salt. This makes it less of a budgetary constraint and much more of a practical one.

I’m not going to respond with a lot of depth because I don’t think I have a good enough understanding here to be particularly helpful, but I suspect a collar would be considered as inappropriate in a school because of its strong association with BDSM practices alongside the general societal expectation that one’s sexuality is kept out of the public eye. I think that notion can also apply more broadly to the situation as a whole, at least to an outside observer.