Yes there commercial jobs out there, yes there are big names that use it, but it’s an increasingly insular community, it’s ceased growing, a lot of people have moved on, and it never really found a niche.
Established programming languages never “die” in the sense of dropping to zero, but to the extent that the question is meaningful, Clojure’s dead.
Linked here alongside other resources: https://clojure.org/community/resources
Oh, and there's a #clojure-dev channel.
There are many ways to contribute to Clojure and its ecosystem: https://clojure.org/community/contributing -- and a PR or patch is often the smallest, simplest part of the process because there is a lot of other work involved in making any change while maintaining stability and performance.
Clojure core and Contrib libraries use Jira for collaboration (and GitHub for hosting source code). Anyone can post to https://ask.clojure.org (maintained by the Clojure core team) with suggestions about changes, enhancements, bugs, or even just general questions. The core team and the various Contrib library maintainers are quick to create Jira issues from posts there.
Once all the groundwork has been done on an issue and it is ready for a potential patch, you can get a Jira account approved (if you're a first-time contributor) and you can attach a patch to a ticket there. See https://clojure.org/dev/dev for information about the development process which emphasizes the groundwork necessary for a change to be considered. Many hundreds of people have gone through this process: https://clojure.org/dev/contributors
Anyone can sign up for the Clojurians Slack at http://clojurians.net -- Slack itself forces the "invite" machinery on us but that self-signup link is well-publicized and, like many OSS community Slacks, is maintained by a team of volunteer moderators. Clojurians is on a Pro plan so it has full history/searching available, sponsored by Slack itself (much appreciated by the thousands of Clojurians!).
Disclaimer: I've been a contributor for about a decade. I've contributed to Clojure itself (a small patch for one release) and I maintain five of the Contrib libraries, which all use Jira and patches as their workflow.
Everyone can join the Clojurians slack, it is a very welcoming place, also to newcomers, in my experience.
Everyone can create issues and patches, getting them accepted may take a long time, but the core team does a great job of maintaining high quality and not breaking things.
I’d rather Clojure have a nice open tracker system you can submit issues/PRs to instantly (without preapproval) like most Github/Gitea-hosted OSS projects do.
And they wonder why no one has solved the curse of lisp?