Yes, gn is less good than bazel for a variety of reasons, not the least of which is tooling like `blaze query --output=build` and the more restricted evaluation model in starlark which is easier to evaluate.

Since starlark and bazel restrict the amount of "weird" things you can do, type-inference is pretty straightforward (moreso than in regular python), since almost everything is either a struct or a basic type and there isn't any of the common magic.