It's worth noting that the term ブラック企業 is now a kind of buzzword and a general slander that carries little meaning. I can see why people like using it because the sound it makes in Japanese is mildly shocking and tarnishing.
- Unreasonable hours
- Distinct social pressure to not leave before your boss
- Non-optional drinking after work
- Absurd drinking rituals (ex. when you cheers, your cup must be below the more senior employees, a senior employee's cup near you should never be less than 80%)
- Threat of being randomly reassigned to a distant town if you get on someone's nerves
- list goes on...
I think one of the only exceptions I know of is Nikon, I've heard they don't have such strict/crazy practices. Trying hard to think of more exceptions, but I can't, so maybe you're right :\