OTOH, the original 2 detectives in Law & Order: Criminal Intent are based on Holmes & Watson (with a generally more competent Watson analog). He had his own Moriarty-esque opponent who was in 4-5 episodes. When DiNofrio stepped away for a while, Goldblum’s character provided a similarly hyper-competent detective with different flaws.Since you used Sherlock Holmes as an example, one of my favorite "mainstream" TV shows in reasonably recent years was based on a modern-day Sherlock Holmes. No, not that self-indulgent thing with Benedict Cumberbatch. I'm talking about Elementary, the show that moved Sherlock Holmes to New York and had Jonny Lee Miller and Lucy Liu in the main roles. It was awesome, and would never have happened if Sherlock Holmes had still been copyrighted.
They told stories “mostly“ original to the show. Great show, and would have been completely legal even if the original wasn’t in the public domain.
And as I noted above, Superman is still in copyright, and there are literally dozens of versions of him in DC comics and in the universes of their competitors.