I have not read the books that the Perry Mason original TV series (1957-66; TV movies 1985-1993 reprised the role) was based on. Perhaps the original books were set post WWII and this series is trying to recapture the original books?
The books may have been set around that time (post-WW
I, not II. I believe the new series is supposed to be early 30s/depression-era LA based on the look of everything) but it's my understanding that Perry was never just a detective in the books. Always a lawyer. Though the first book, "The Case of the Velvet Claws" apparently had no courtroom material at all, it was still meant to be a law-based and lawyer-based story with at least the big 3 members of the traditional cast all more or less occupying the same roles they had on the TV series (Perry as the lawyer, Paul Drake as the PI, Della Street as Perry's confidential legal secretary/aide). Earle Stanley Gardner was a lawyer by trade before he started writing, and based on what I've read his specific interests in law heavily informed what he wrote into the Perry Mason works. He wasn't a detective, police or private, and he stayed within his wheelhouse of familiarity and expertise when writing his material.
What's more is that in the 40s and 50s there was a Perry Mason radio series that was known somewhat for deviating from the focus on the novels and having a greater interest in detective work and exciting action and less (at times almost no) focus on courtroom drama. Stories I've seen suggested that Gardner
hated this and detested the further meddling that network heads acted upon the series, so that when it was due to be adapted by ABC into a TV series in the mid 50s as most popular radio shows of the time were doing in order to survive, and Gardner found out that they were going to make further changes to the series to make it "more suited" for the TV audience, Gardner balked and refused to license the rights to the Mason name and all its associated IPs to ABC.
So ABC took the work they had done, scrubbed off all the Perry Mason related names and markings, and created the show anyway under the name "The Edge of Night". And it ran as a daytime soap for 30 years. until the 1980s. It even, for a time, starred John Larkin (the radio voice of Perry in the final years of that incarnation of the show) in the primary role of the character who was their Perry Mason in all but name. But it was about a detective-turned-lawyer who fought for his clients and was more involved initially in the street-level goings on of the cases. In fact, it sounds a hell of a lot more like what this new series is supposed to be than Gadner's books or the eventual Mason TV series/movies.
The CBS series only came about because the studio agreed to let Gardner have a more active role in shaping it, up to and including the fact that he basically hand-picked Raymond Burr for the title role based on the auditions they reviewed and in spite of the fact that studio executives were not keen on Burr in the part (believing him to be ill-suited for the role since he was normally known for playing 'heavies' in noir works and the like) and had designs on more traditional hollywood leading men. Gardner was seemingly so supportive of the series that he allowed them to adapt several of his shorts and novels into plots for episodes and he even appeared in the series finale in a cameo as the judge for the final case that was tried.
Don't get me wrong, this new show might turn out to be interesting. Noir-ish classic detective yarns are always fun. But it can be a good series and a bad Perry Mason work at the same time.
Maybe they would've been better off if they had adapted a proper detective source material instead, like Sam Spade, Philip Marlowe, or Barrie Craig. Hell, this seems like it'd be right up the alley of a Philip Marlowe type mystery since it's set in early-20th-century Los Angeles.
