Elaborate on note about unmaintained state in README

Author: chriskrycho

README.md

@@ -15,8 +15,10 @@
   </a>
 </p>
 
+---
+
 > [!IMPORTANT]
-> **Volta is unmaintained.** We recommend migrating to [`mise`](https://mise.jdx.dev/). See [issue #2080](https://github.com/volta-cli/volta/issues/2080).
+> **Volta is unmaintained.** Everything that works today should continue to do so for the foreseeable future, so if it is working for you, there is no particular *urgency* to migrate to another tool, but we will not be able to address breakages from new OS releases or other changes in the ecosystem, so you should put it on your maintenance roadmap at some point. We recommend migrating to [`mise`](https://mise.jdx.dev/). See [issue #2080](https://github.com/volta-cli/volta/issues/2080).
 
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