> they actually enjoy popularity in programming languages today They have enjoyed popularity amongst the Scala FP minority. They are not broadly popular as th

> they actually enjoy popularity in programming languages today They have enjoyed popularity amongst the Scala FP minority. They are not broadly popular as they come with an unacceptable amount of downsides i.e. increased complexity, difficult to debug, harder to instantly reason about, uses far more resources etc. I have built many applications using them and the ROI simply isn't there. It's why Odersky for example didn't just bundle it into the compiler and instead looked at how to achieve the same outcomes in a simpler and more direct way i.e. Gears, Capabilities.