I did read your post (between patients).
It is supposed to be a matte Grey finish. (matte Nickel on Brass ?)
That finish is relatively soft, but would not wear everywhere to a glossy silvery finish, like on the production examples you show us. Caseback, sides, bezel yes.
But there should be plenty of matte areas left.
Frankly speaking, I can not see the matte finish you can see.
This one looks brushed:
Just to compare, a matte grey finish:
I think those watches have been polished.
Or, they were manufactured Glossy.
A normal B-uhr was used for much longer periods, and should exhibit much more wear, and the only glossy ones are the ones that have been polished. Of the 20+ examples I have seen over the years for sale on various auction houses (incl Ebay) the vast majority are still matte, even if they are heavily worn.
At the moment, there is a well worn Laco B-uhr on the German Ebay. Looks like ...., but the surface is still matte!
There is a possibilty that they used a different plating metal, but that sound strange.
Still, I do not think this issue does matter much. We can do what we like, right??
We have the following options:
Sandblasted (matte grey, standard Laco finish)
Polished
Brushed
Personally, I think more and more the polished surface looks cool...
The Laco drop lugs do look fine.