The whole reason Elm has been stuck in a niche when it had _huge_ hype around 2015 and everyone was sure it would be the "next big thing" on the front-end is that the developers have tried to keep full control of the language and keep shooting down proposals by users. It's either their way or the highway.
I went through and collected up the reasons to do it, distilled it down and gave examples as requested by the core team and got lots of positive feedback from the community, and just got no response from the core devs and nothing happened.
I agree not all changes people propose are good, I like the fact the language is opinionated and doesn't include half-baked ideas, but there is literally no way to get anything through into Elm core, any attempt to do the legwork is just ignored and thrown away. It is a one-man project and that's it, but they pretend that isn't the case.
Honestly, the answer is probably an unstable fork of the language for more experimentation and development, which to be fair, anyone could do¸ but obviously maintaining that would be a lot of work (I don't want to imply that the core Elm team have some responsibility to do it).
I even got a proof of concept working and showed it off in the Elm Slack.
And then I got told my library would not get accepted on the official package repository because the core team was developing their own "correct" abstractions for the main Web APIs and they did not want third-party libraries to compete with the core team's libraries, as regular web developers don't know what they're doing and are incapable of choosing the "right" abstractions, which apparently only the Elm core team is capable of doing.
That experience turned me off Elm for good.
Flash forward to 2020: There is still no "official" Web Audio library. (There are a few non-official ones on Elm Packages)
It's your right to side with the core team, but they're the ones pretty much killing the language's chance to see any real usage.