(Googler, opinions are my own) Similar to the peer comment to me, Dart languished for a long time. You have to remember Dart was created as a replacement for

(Googler, opinions are my own) Similar to the peer comment to me, Dart languished for a long time. You have to remember Dart was created as a replacement for Javascript and that they wanted other browsers to embed the DartVM in their browsers. This got absolutely rejected by Mozilla, Apple, and Microsoft. They then attempted to use it as a transpiled language, but it always generated larger javascript files than most other solutions. It still exists and is used, but Typescript ended up being a better solution. (note: there is AngularDart, which is a bit of a fork/mirror of Angular, but for Dart). This has some uses within Google as I understand it, but it's usage outside of that is rather small. Flutter using Dart ended up being a large boon for the language and drives much of the changes to the DartVM. Dart had to go through various targeted usages before it really found a home.