In the past it used to work the way the parent comment is describing. The confusion is understandable. Apple basically got rid of macos and replaced most of it with things from ios in 2020, a lot changed.
True, although the i2c controller that the dimms are connected to is an entirely separate device from the i2c controller in the gpu that's connected to the display ports. As long as you know what you're doing the risk is not significant.
Fun tip: the same process works to modify the edid stored on a typical monitor or laptop screen. Sometimes you can even change various settings on the tcon by writing to other i2c addresses. You also don't need a raspberry pi, any computer works.
You can't even turn on and use a new apple product unless you phone home and ask apple for permission. I'm not sure why this is newsworthy. Apple products are known to phone home more than just about anything else. It would be more surprising if apple photos didn't phone home.
Can someone fill me in on this? What hoops have to be jumped through? The last time I used macs, there were no issues downloading and installing older OS versions, but I have not used them recently.