So I'm on my fourth Mac (second Intel-based), and for some reason, more often than not (and I mean way more often), the WUs end up being cut short being told "Error while computing." Does anyone know what might be happening? (I have a hypothesis.). And, am I the only one?

Those hadcm3s models never ran well on Macs.
As well, there is a bug which prevents the trickles being correctly returned, so no credits, and Apple is shutting down both 32 bit support, and soon, the use of Intel style processors.
(See my post here), so there's no incentive for continuing to create and maintain Mac programs.

so there's no incentive for continuing to create and maintain Mac programs.

Even though I have never used a Mac, that seems a shame to me, especially as at some point the percentage of other computers such as Linux and Windows using RISC based chips may also rise.

Qualcomm and Cavium have introduced ARM-powered servers that have significant power savings, with tests by CDN operator CloudFlare showing equivalent processing power at about half the power consumption of Intel processors.

Taken from the article about Mac's migrating to ARM based processors.

Finished my first and only project since January. It was projected to take three days, but it took five. So my fingers were crossed because others had crashed after only several hours. It's a shame that Mac users can't really be of much help for CP.