This series is set in an Alternate Universe in which Holmes doesn't have a mood disorder.
Which changes a lot. He never developed a cocaine habit because he didn't have the incentive to self-medicate. His somewhat more amiable overall temperament in this adaptation is a combination of less hostile brain chemistry and the absence of the psychological side-effects of drug use.- This troper, who grew up in the Soviet Union, would suggest this is very likely true as an Enforced Trope. Soviet media watchdogs would not appreciate dealing with mental illness, let alone cocaine!
