Sorry, looking back at my wording I can see how that's confusing. You are correct. PipeWire replaces the standard JACK libraries with its own ABI-compatible implementations. This allows any JACK-compatible application to support audio through PipeWire using the same APIs it would normally use for JACK. This is also how PipeWire handles support for PulseAudio, ALSA and other multimedia libraries; it kinda reminds me of Wine for Linux audio protocols, if my understanding is correct anyway.
To use PipeWire in place of JACK, you have to install a specific package (`pipewire-jack` on Arch Linux) and run all of your audio applications using a wrapper command called `pw-jack`. You can update the `.desktop` entries for audio software on your system to automatically run this command; I've done that and everything I use launches correctly, tbh I forget that PipeWire is there. I just use Bitwig, qjackctl, Catia, etc. and they all think they're using JACK but really everything is being handled by PipeWire. Pretty kewl and it's been working perfectly for me for quite some time. :)
To use PipeWire in place of JACK, you have to install a specific package (`pipewire-jack` on Arch Linux) and run all of your audio applications using a wrapper command called `pw-jack`. You can update the `.desktop` entries for audio software on your system to automatically run this command; I've done that and everything I use launches correctly, tbh I forget that PipeWire is there. I just use Bitwig, qjackctl, Catia, etc. and they all think they're using JACK but really everything is being handled by PipeWire. Pretty kewl and it's been working perfectly for me for quite some time. :)