Not sure if I have just spent too much time in the JS/TS world and so I have forgotten the pain in this area in proper compiled languages, but to me it seems like needing "typed holes" smells like maybe there is some abstraction missing in your codebase.

I prefer to have code layered in a way that my inflection points happen across well defined interfaces. Then I can make changes one layer at a time in increments that are small enough to still be able to reason about. But maybe I am totally mising the point of typed holes!