Yes, you can do that, but it's pretty obvious that if you want garbage collection everywhere, you're not going to use a language with linear types and optional,

Yes, you can do that, but it's pretty obvious that if you want garbage collection everywhere, you're not going to use a language with linear types and optional, pretty much discourage GC, and write type synonyms all over the place (or fat signatures), you're going to go for a language where it's natural.