Honestly, despite my experience in standalone programming and algorithms, my experience in web development is limited. I've had experience with ASP dot NET, Actix (Rust framework Lemmy is powered by) with Diesel ORM, and PHP. ASP is limited in .NET ecosystem, and the primary IDE to develop ASP dot NET apps is proprietary, not something I want to work with. Actix is doing pretty good, it uses Tokio internally, one of the fastest and most robust async frameworks in the wild. I've been using Rust for more than 2 years, and I'd be honest: it was designed for medium- and large-scale application development. For making prototypes, you probably want another programming language. And I see PHP as one of the easiest ways to prototype.
For Django, I've never used it, maybe I'll have to use someday. Nevertheless, I see Python as a rather bloated (in terms of overlapping language features) language which suffers from similar problems as PHP, like no type checking (by default). Also, Python packages are tied to some exact version of Python, which causes a large dependency mess when using multiple packages (Rust also has this problem, but at much smaller scale, and developers of packages often use conditional compiling of language features). Meanwhile, I think that some Python problems could be resolved using a package manifest file, like Rust does.
If you have something to add, go on, because I'm always thinking what server language/framework I should use for my Next Big ProjectTM.