It would help, yes. Here's one of my projects, that uses different subdirectories in target/ based on compiler options pre-commit runs:
$ du -hcs target/
190G target/ $ du -hcs target/
190G target/It's been a journey...
Do you have some more info about the codebase, is it public?
One of the big slow downs comes from a single crate (async-stripe). In retrospect, I should just use reqwest and serde to do everything with Stripe's API manually and not use any crate at all (especially if it cuts the build time in half).
`actix-web` itself should be fine, `sqlx` can be heavy if you use its compile time features, I'd assume `askama` is heavy as well, just based on the description (it generates rust code at compile time).
Otherwise it depends on how the code is structured (e.g. how generic it is, how deep types or complicated futures it creates).