Given that a 7MHz Amiga 500 could mix eight tracks in CPU in real time, this is a very sad state of affairs. Your M1 is how many thousand times faster?
VSTs didn't even exist when Amgias were relevant. Each of those tracks was not running a virtual synthesizer, convolutional reverb, parametric EQ, compressor, amp sim, etc.. A modern DAW is simulating an entire studio worth of hardware, not just an eight channel mixer. One of these laptops can mix hundreds of tracks without issue; it's the plugins that require more power.
Are you sure that what the Amiga was doing with 8 tracks is equivalent to what Logic is doing? I'd guess there is more to compare than just the number of tracks involved.
Yes but I think there's a point: hardware horsepower is undoubtedly capable of handling such workloads. I'm not knocking on Logic, but for 'fun' projects especially I find it impossible to believe that the hardware listed is the problem.
There's a chance it's a logic bug or one plugin having some issues, I suppose
All plugins are certainly not made equal. Some I've used are surprisingly bad performance-wise for what they do, while others are just genuinely computation-heavy.