(replying from different account)
Hm - I think Joaquim might be right here. I also found this old thread on the forum by @KristofKoch on the same topic that references the issue @Joaquim referred to.
See also this MacOS (Pre-Apple ARM processors) and this link on macos multiprocessing - the latter one says:
Unlike Asahi Linux, macOS doesn’t provide direct access to cores, core types, or clusters, at least not in public APIs. Instead, these are normally managed through Grand Central Dispatch using Quality of Service (QoS) settings, which macOS then uses to determine thread management policies.
Cheers,
Christian