Sherlock Holmes in the 22nd Century/WMG

The process used to bring Holmes Back From the Dead permanently dyed his hair from black to blond
Yes, this requires ignoring the Victorian flashbacks when Holmes' hair was blond as well. But his hair does appear to be at least a dark shade of brunet when he's shown in suspended animation.

Holmes' is in denial about Robo-Watson's status as a Replacement Goldfish
Overall, he tends to treat Robo-Watson as the geniune article. But there are little moments when he catches himself, such as when he refers to the Victorian ages as 'their time' before correcting himself. Considering that Canon!Holmes once called Watson his only fixed point in an ever changing age, it's not that surprising that he'd cling to the closest thing he has in an unfamiliar environment.