Yes, and Bazel makes some very serious trade-offs in order to make starlark work. Notably, dependencies are referenced as stringly labels as a poor substitute for lazy evaluation (starlark itself has strict evaluation semantics).

This in turn requires additional tooling to catch errors early, and also means that a starlark-repl for Bazel will never really be all that useful, since the build graph doesn't exist in starlark alone.

In my experience, this makes Bazel a significantly harder build system to truly grok, tho perhaps easier to use it without understanding it.

Contrast with nix, where the entire build graph exists as a nix expression. In my experience, you can gain a surprisingly deep understanding of nix armed only with knowledge of nix-the-language (and without knowing any implementation details of nix-the-binary-that-builds-derivations).