Edit: "Sprague" or Sprague Thompson is rolling stock dating back to 1908. There are one or two hidden very well in the system, with one still in mint, serviceable condition.
That particular train of Spragues, the one that is covered with paint, has been stored in many places over the years, without a clear intent as to its future, like the BOA prototype. The first time I saw it was in the Vaugirard yard, which wasn't exactly a walk-in, so that made it a hard target compared to the regular trains. When they moved it in the connexion between lines 7 and 10 it became a much easier target and a go-to place for just about everyone.
I'm afraid the RATP doesn't care much about that specific train.
As for types, yes, we have all of them. Very few of us care about historical importance but it might actually be more of an attractor than a detractor for those who do.
Couldn't understand if this specific one was "spared" for so long because it was well hidden, or because most painters considered it "too nice" to paint (or pointless, as it was rarely in service..)
The other ones (Monceau, etc) were obviously well and truly rinsed.
There's a few nice examples of preserved rolling stock in the RATP's "secret warehouse", but they only kept the head and trashed the wagons.
Vaugirard was definitely a nice yard, hard until we found a nicely hidden trapdoor-in-a-wall behind a 03..
Vaugirard was more of a "monte-en-l'air" business for some of us ;-).
And sure, les ateliers seemed to be affairs of bras-honneur ..
This is backwards: it's the graffiti vandals that don't care.