IMHO the term is a denigration of R” Moshe ZT”L. It makes it seem as if he ?”? fabricated something which did not exist.
In Rav Binyomin Forst’s “The Kosher Kitchen” (page 311), the author points out that the term “chalav stam” is used. He makes no mention of it being in any way degrading to R’ Moshe ZT”L.