Both the Rationalist community and the Rust community are very active in pursuing their goals, and unfortunately, it's far easier to criticize others for doing things than it is to actually do things yourself. Worse yet, if you are not yourself actively doing things, you are far more likely to experience fear when other people are actively doing things as there is always some nonzero chance that they will do things counter to your own goals, forcing you to actively do something lest you fall behind. Alas, people often respond to fear with hatred, especially given the benefit of physical isolation and dissociation from humanity offered by the Internet, and I think that's what you're seeing here on Hacker News.