Our academic program equipped a lab with those "trashcans" in 2014, and they were incredibly reliable performers. We have since equipped that lab with Threadripper PCs, which are great. But when COVID hit last year we were able to loan out the "trashcans" to students who were able to complete their animation projects largely at home, and remote into the lab to take advantage of the threadrippers for extra rendering potential.
So, I don't hold to the hatred that those machines get. They were clearly an evolutionary dead-end, but they were well-built and reliable.
The notion that the M1 will be "tuned for blender" is bizarre, frankly. The opposite is true: with this investment, Blender will be tuned for the M1, the same way that Octane and Redshift are now tuned for the M1. The groundwork that Apple laid with developer support for Redshift and OTOY will now pay off in the adaptations of Cycles to the Metal framework.
You could actually make the case that the M1 is tuned for the workloads that Apple likes to think are the province of their Pro customers; this is evidenced by the silicon support for ML, and advanced video encode/decode (including ProRes).