Ultra low? Wow, not sure why I'd want to spend money on a game that will only give me FPS in the 40 range at ultra low.
Looking on Ubisoft's site, and it appears that ray tracing is the cause of the performance differences between Macs and PCs. If you want selective ray tracing you can "get away with" a M1 or M2, if you want to use standard ray tracing, then you need a M3 or M4 - and then in both cases you only get 30fps - this of course is prior to ultra-low preset update.
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