But! To each their own!
For example, if I wanted to say, return a 500 status code for all diesel database errors, I can convert the diesel error into my custom error type, then throw it back up the stack using `anyhow`. This works _really_ well in conjunction with Rocket's Responder impl.
EDIT: This is pretty close to what TFA is saying as well, I should have read more in the article, heh
You can absolutely do that if you want, it's just that usually when writing an executable you don't care about creating the precise error types thiserror provides (especially doing so executable-wide), you'd handle the errors you get from reqwest or sqlx or whatever when you get them, and those you don't handle you just want to bubble up to an executable-wide handler.