I have Audacity 2.3.0 and it will shut down when applying chains/macro and I don’t know how to fix it. I tried removing it completely from my computer a few times and deleting accompanying libraries etc. but everything still happens repeatedly.
When I reinstall things I can’t seem to find any of the files that seem necessary like the audacity.cfg/xml and others as shown in the image below.
I presume that you know that Noise Reduction is a two pass effect, and that it does not currently support custom settings in Macros.
Try running each of the effects in turn manually to a long track and see if Audacity crashes. That may show where the problem lies.
I can’t reproduce the problem, but I’m on 64-bit Linux, so the problem may be specific to 32-bit Audacity on macOS.