So if a language can't do HTTP and async I/O (with state-of-the-art performance) then we shouldn't consider any other possible application for it? Rust is not Java, you have better languages to build webservers with.
Yes, if a language can't easily do async IO and HTTP in 2018, it is in deep shit with regard to long term adoption. The Rust devs realize this, otherwise they would be putting less effort into tokio.