Can confirm this is true, however you should find that subsequent compiles are much quicker unless you’re doing something unusual.

If you’re just changing JavaScript it should be more or less instant (you may not even need to recompile, hit R in the packager console or use hot reloading). If you add a new native dependency or change some native code, it will have to recompile any affected parts of the code but you should still see much quicker compile times than from a clean state.

I find building react native apps much faster than building native apps. You don't need to recompile if you're just changing the javascript, and only a couple weeks out of the year have I actually needed to change any native code.