Looks like germans tried to just fire quickly enough, thinking it does the job. Don't think they ever thought about actually being able to produce it in the same or more quantities than the Allies to do the job done. Why would they ever need these "versions" of MG34 and MG42?
MG42 whole purpose was to have an MG that could be mass produced with stamping technics.
To fit different tasks.... supression, anti aircraft fire, focused fire...
MG34 were mostly used in Tanks cause u can change the barrel from inside, and MG42 u can cause its a side mechnism.
https://www.youtube.com/watch?v=_8Rka0k1Wp0