I know. I’m asking if it goes bad, how would you even know when the smell is bad before it is rancid.

You'd be wise to be careful with stinky tofu, at least in many places.

The safest methods simply marinate tofu in fermented amaranth; the tofu itself isn't aged. But there's many approaches to it with and without questionable safety practices. I'm not sure comparisons to blue cheese or koji-fermented products are appropriate.

https://roadsandkingdoms.com/2019/stinky-tofu-in-shaoxing/