In JMonkeyEngine v3.5.2, the “jme3-lwjgl3” library should automatically pull in OpenAL binaries for both Intel macs and ARM (“Apple Silicon”) macs.
However, the diagnostic message doesn’t actually mean that OpenAL is unavailable. I think it’s saying that the ALC_EXT_EFX extension feature of OpenAL isn’t present. That probably has to do with limitations of the audio drivers on your mac, or maybe the hardware. Basic audio functions might still work.
If ALC_EXT_EFX extensions are important to you, you might try upgrading your operating system to the latest version and making sure you’re using version 3.5.2 of “jme3-lwjgl3” library.