Just as a note w/rt JACK, I run AV Linux (built on MX/AntiX), and the JACK server comes configured as 44100 Hz sample rate. Additionally, for reasons I have been completely unable to comprehend, when I run "pure" AntiX in a VM that is hosted on Win10, the VM appears to default to 35020 Hz sample rate, which is absolutely bonkers.
I mention this because I am still working on JACK MIDI (having a day job can make things go very slowly) and I've just gone through about a month of figuring out that JACK had a different sr than PortAudio which was causing my PD instance to ultimately experience a lot of overruns. This all mattered because I am still working to get the MIDI to sync correctly between PD time and JACK time.
Do I have an opinion on the default sr for PD? Not really. I just want to point out that this is not a "no consequences" kind of decision. For the future, I am pretty much continually running with pd -r 44100 just to make sure. If you do change the default, it might be good to light up a billboard saying how to get the old behavior back :)
D &cet
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