Perhaps because Express & Koa were "good enough" there never was a large enough momentum behind say SailJS to make it work. Nevertheless my experience with ORMs or scaffold generators has been that I always feel they are one custom use case away from turning from time-savers to time-sinks. When you write your own SQL and implement your own models/services or whatever abstraction you decide to use, you get a much deeper understanding of what is going on than just trusting your framework to do it for you. And is that good or bad? That is certainly a topic for debate.