For a brief amount of time I thought Dart would eventually push through in the web. It was interesting to see it's resurgence in the domain of mobile recently though.
On the other hand I didn't exapct Go to go anywhere. I remember briefly paltong with it a few years before it became popular and kinda just set it aside because I thought it was just some random toy language from Google.
I actually tried to adopt Dart v1 line at a startup buying into the WebComponents (too) early. The weekly updates broke compatibility so much and often that it had to be abandoned. Just as well as it didn't survive or perhaps because.
Yes, Go picked up pretty unexpectedly. But now I believe there are good reasons for that. Though I do not expect core Java developers to accept it anytime soon.
I knew a few people who were really into Dart before flutter, back when you could use Dartium to run Dart code in a browser (for testing and development only) without transpiling. I dont know if was ever based in much reality, but a few of them were convinced that Google was planning to eventually put a full Dart runtime in the mainline Chrome browser. There may have also been rumors spread about an earlier Microsoft Edge doing the same, if I'm recalling correctly. Of course, none of that never happened.
On the other hand I didn't exapct Go to go anywhere. I remember briefly paltong with it a few years before it became popular and kinda just set it aside because I thought it was just some random toy language from Google.