Thank you for this article, I am the author of @dominokit which domino-ui is part of, I am using GWT in a big project, 264+ screens, around 100K LoC, running in production in 14+ sites, The team started with 2 developer working on both frontend and backend, then reduced to 1 developer since it was enough to keep up with a 10+ backend developers adding features to the application.
We have great look and feel UI, excellent performance, the is compiled and jzipped on the wire to just 800KB, and most important excellent maintainability, we can get any #java developer to ride in in few hours when we want.
GWT have never been dead, we got version 2.9 recently with java 11 support, and 2.10 is coming very soon, and after that we are doing java 17 support and add language features. we already implemented some thanks to Colin Alworth.
The community around GWT despite being small but it is a very active community, try to ask a question in the gitter channels or in the google group and see how fast you will get the answer.
The tools and frameworks around it have also been under heavy active development, those are modern tools and frameworks that covers almost every aspect if web development, and you get it all with one stack, Java.