> In July 2019, after the release of version 2.13.0 of the Scala 2 compiler, and with Dotty (Scala 3) already in advanced state of development, the authors concluded that the TypeLevel fork had served its purpose. New contributions are best forwarded to the Lightbend's compiler fork.

>> The way I see it, the TypeLevel compiler was very useful for trying out and refining features that have found their way into the mainline compiler afterwards. (by Martin Odersky

As a Scala user (with not much awareness of the big players in the community), I think the fork worked out nicely. I enjoy the features in Scala 2.13 that were stimulated by the fork. With the impending release of Scala 3 it probably made even more sense to discontinue the fork rather than use it to seed more new features.