I'm not sure soap scum increasing corrosion is a concern.
The razor base material and the plating is important.
I have both personal experience and knowledge from the forums. I have several vintage Gillette razors that were made in the 50's and early 60's. The base metal of these is brass. I think the plating is nickel, but I haven't confirmed. They were very dirty with soap scum when I acquired them. Some soaking in scrubbing bubbles and a little brushing with a tooth brush and they cleaned up nice.
I have a Fatip that is nickel platted brass. I let the soap scum build up on it and only once in a while clean it with a soak in warm water and dish detergent and soft bristle tooth brush.
For these plated razors I would be more worried about the cleaning than the soap scum. The plating is very thin. If the plating is gold then it is also relatively soft compared to chrome or nickel. You don't want to rub or scrub through it. That is why I said soft brush and don't brush any more than necessary.
The razors that are made with Zamak alloy (e.g. Edwin Jagger, Merkur) as the base metal are a different story in a way. The issue with these is you must be extra careful with the plating. If there is a break (chip, flaking, wear and tear) the Zamak will corrode away fast.
FYI to anyone, I learned a lesson with my first Edwin Jagger razor. Starting with second Edwin Jagger I rub soap on the cap threads when I change the blade to help prevent the chrome plating on the threads from chipping and flaking and exposing the Zamak base.