the biographic summary in Pelloch' 29 mentions a Jean Leroy. He collected testimonies about Atget, and with many of his photographs, made it into a small book in 1975: "Atget, magicien du vieux paris en son epoque." ISBN 10 : 2904732500 , a reprint in 1992 ISBN 13 : 9782904732508
the conclusion in that article points to former photographers of Paris:
"D’autres photographes firent, par le passé, un travail similaire, citons : Nègre, Le Secq, Maraille. Ils furent de bons photographes mais ils n’avaient pas cette petite flamme qu’ont les grands artistes, leur capacité d’émotion et leur vision poétique du monde. Cela ne s’apprend pas, Atget avait cette grâce mais il a disparu sans savoir qu’il était Atget."
as I don't know how to render this correctly in English, I went to deepl, that produces this:
"Other photographers have, in the past, produced similar work, such as Nègre, Le Secq and Maraille. They were good photographers, but they lacked that certain spark that great artists possess: their capacity for emotion and their poetic vision of the world. That is not something that can be learnt; Atget had that grace, but he passed away without realising that he was Atget."
it is indeed interesting to compare with predecessors. Charlès Nègre and Henri Le Secq were some of the first who started working on Daguerre process of 1839. Nègre lived some 20 years in Paris and did "street photography" and some architecture. Lenses he had were pre-rectilinear, these appeared in the 1860's.
This is by Le Nègre, picturing Le Secq with a little girl, giving some money to a street musician, in early 1850's:
just to illustrate what "old" is "old" in Paris.
At the time of Atget, Haussmann reshaping was accomplished since long (1870), so the old preserved in pictures by Atget was in part more about decorative architecture that is prone to disappear when real estate business or trends redo things, in part the old jobs that vanished as industry and technology were replacing them.
Nègre instead could take pictures before Haussmann plans started demolishing streets and houses.
This was a street that disappeared, rue de la Tixéranderie, in 1851.
The street track itself existed in the 12th c, the houses there of course not, but 17th/18th c.