Rust would be equally unsuitable to this task. Web development in C++ or Rust? Why?

There may be some advantages to writing a middle tier application server in either of these languages, but using a system language to manage a web front-end is effectively like using a hatchet to shave. Sure, the hatchet is faster at cutting wood than a safety razor, and if one is careful, it could be used to remove stubble, but chances are that one is not clearly thinking about the problem at hand to suggest such a tool.