fwiw - darktable 3.8.1 runs for me on macos 10.13.6 (2011 17" mbp) and macos 10.15.7 (2013 27" iMac). App launch takes some moments on both, but responsiveness and performance is fine+ once running. Imports (without copy) works well enough for me. The *collections* and *film rolls* I've imported from non-local sources (NFS, SMB, ssh/sftp) 'complain' with a strikethrough on re-launch, but the thumbnails and metadata remain present locally even when disconnected.