Sir Arthur Conan Doyle created Holmes back in the late 1800s. Everyone can read his books, see the movies. Sherlock Holmes has become a kind of icon.
Were one to do a television program about Sherlock Holmes they would either have to turn one of Doyle’s books into a series, or run the risk of creating new adventures which might go outside of the parameters; that is, canon.
Recently, there have been two programs; Elementary and Sherlock which have cast the character in the modern day. Although there are a few references to the past, in both cases, the main character fits into expectation.
In short, whether the series stars Benedict Cumberbatch or Jonny Lee Miller; they behave as one expects from Sherlock Holmes.
This has allowed both series to survive with little discordance.
This is not true with Discovery; which is often referred to by its initials; STD.