Yes, other than ones that were gold plated or had a special finish... Most of the common machines had nickel plated cranks and because they were handled a lot, plus they are 90-100 yrs. old, the plating wore off and they got rusty. You can remove any rust and polish them if you want a shiny crank, they are relatively easy to restore...
"The phonograph is not of any commercial value." Thomas Alva Edison - Comment to his assistant, Samuel Insull.
"No one needs a Victrola XX, a Perfected Graphophone Type G, or whatever you call those noisy things." My Wife
Right on that--and unfortunately, taking them off the machine only reveals a lot of nice shiny nickel as a contrast to the rust & pitting on the outside.
I had a very rusted and pitted crank. I used 220 grit to smooth out the pitting, then 400, followed by emery cloth. Then i replated (easy tutorials on YouTube). I don't have a picture of the finished crank on my phone, but it looks new. Here's a No. 2 bezel that i did the dame way.