The point is that making a typesystem sound is really hard and requires trade-offs. I think Scala is a wonderful example. Check: https://www.baeldung.com/scala/

The point is that making a typesystem sound is really hard and requires trade-offs. I think Scala is a wonderful example. Check: https://www.baeldung.com/scala/dotty-scala-3 https://www.baeldung.com/scala/dotty-scala-3 To quote from there: > Scala 3 has dropped some unsound and useless features to make the language smaller and more regular. It has added some new constructs to increase its expressiveness. Also, it has changed some constructs to remove warts and increase simplicity, consistency, and usability. Some of the features they dropped because they were unsound were still useful (to me). Typescript tries neither to make their typesystem (perfectly) sound, nor to make it as elegant as possible. That results in it to be very useful/pragmatic for everyday-programming tasks.