This post isn't in response to what anyone here has said, but something to think about. Maybe.
"Obscure" is a word that is pretty relative. Actors who might not be known to the general public (via TV or film) are well known to many casting directors, directors and producers of plays all over the country or work for a season or two at a regional theater. These actors make their living touring in productions from Broadway, developing plays with fellow actor/playwrights, teach the craft at theater training schools and work as artist-in-residence in various school programs from elementary school through college. As crazy as it might sound, there are actors who will do some TV work (commercials or an episode) and a film here and there for a shoot of really good money but prefer to stay involved in the theater and the kind of work I mentioned above.
Not that long ago, I read on an entertainment board a post by some readers who noted, with sadness, that Jean Stapleton's career after All in the Family just died. How far from the truth that statement was. Ms. Stapleton has done nothing but plays (except for a TV movie here and there) in New York and throughout the US since that show ended. When I lived in New York, she was always in a new play. She really seemed to enjoy being in newly developed works or those that are not frequently staged in a very commercial production.
Most of the public believe that if an actor is not seen on TV or film, they have no career or had no career prior to becoming famous. In the case of DS, several of the actors had decades worth of acting work mostly in theater; John Karlen had quite a bit of TV experience prior to his becoming famous as "Willie Loomis" and later on Cagney and Lacy as "Harvey."
So that's my semi-rant for the day. Just felt like typing.
Nancy