This paper is one part of the long-running threads vs. events debate, and it probably isn't that helpful to read it in isolation. Erlang, JRockit, and Go implemented the kind of scalable green threads proposed in this paper, although I don't think they were inspired by it. Most programmers who care about high concurrency (other than Erlangers) decided to just bite the bullet and accept the difficulty of writing event-driven code rather than try to make threads scale. The fact that people prefer to struggle along with events doesn't negate their difficulty, though.