I'm a little slow, so maybe everyone else already realized this, but after struggling for almost a year with periodic "Two different types with this name exist" error from typescript, I've realized it is actually really helpful error and it highlights a real problem that I've failed to understand until this week.
I've been working around this issue by making sure that my libraries with common dependencies are always on the same version for some of our shared library dependencies. This works because package managers dedup the same version of a dependency. But when the versions diverge you get different instances of the library. In this mode, Good Guy TypeScript is telling us "Hey you're comparing values and types from different instances of the same library and that's a Bad Idea."