I’ve read in a hairloss forum that Nikola Tesla castrated himself so he doesn’t get distracted from his research. Maybe that’s the reason he didn’t go bald. I’m amazed from what you can read today in the internet.
If one is castrated, they will stop their balding process where it was at the time of castration. Taking testosterone can reverse that, producing balding in men with the genetic traits for hair loss (even without testicles).
If Nikola Tesla was castrated (I am not sure about that), then he will not be balding… as shown in these photos at Neatorama. The man was a genius, but he looked like hell with considerable weight loss as he aged (as seen here). He did seem to maintain his hair pattern, even with the weight loss.