In practical perspectives, I’m mostly concerned about computer resources usage; I have computer resources constraints. So using Rust would benefit on that. But it is for a Web application backend. So, is it worth it having to learn Rust + Tokio + Axum, … in this specific situation? Also, that this is mostly for initially prototyping an application. Also considering if I add developers in the future, they would most likely not be familiar with Rust, but with more popular frameworks such as Node.
Because of that prototypes should be small - no more than a week or so worth of effort. Anything larger means it will take even longer to rewrite it from scratch which management will never like and is overall just a waste of time. Most of the time you don’t actually want a prototype - you want a MVP written in the language of the final project as it will become the final product.
Really the only time I would write a prototype in a different language then the final product is when you don’t yet know the language you want to (or more likely, need to) use or you know another language vastly more than the target language. The time saved by the language is often just not worth it overall when you are reasonably competent in both languages.