Now we can understand how a new MacBook Air with 8GB of RAM and a 256GB SSD can seem like a revelation to many users whose 2012 MacBook finally dies.
Actually, in my experience, those 8GB of RAM in older machines are more “capable”, with the lack of a better word. Sure, they are slower RAM modules, but the pressure doesn’t ramp up as quickly as in modern machines.
I don’t know the exact reason, maybe it’s because older MacBooks have lower resolution, or maybe it’s because the integrated Nvidia/Intel graphics needed less VRAM, and the 8GB of Apple Silicon are shared by the GPU, the CPU and maybe even something else, but in my experience, older machines need less RAM.
The 8GB of RAM on my former 2010 MacBook Pro, and on my current system, an Intel Haswell 2014 Mac Mini, give me a good/decent performance, staying almost always on the green zone of pressure. While during my tests with an M1 MacBook Air and an M2 MacBook Air, both of them with 8GB of RAM, they quickly get into the yellow/red zone of memory pressure with the same tasks. Sometimes, they went into the red pressure zone and dropped to yellow after increasing the swap file, and then after a few moments, it would get into the red zone again. I even made screenshots because it shocked me, but no idea if I still have them around.
Also, I had the opportunity of testing one of the last Intel MacBook Pros, a 2017 MBP with an Intel Kaby Lake Core i5, again with just 8GB, and I noticed that those 8GB didn’t give me the same performance as on my, by then, current 2010 MBP. I noticed how quickly it went into the yellow zone although in 2017 I didn’t pay much attention to the swap file, so don’t know if the swap usage was as aggressive as in the Apple Silicon macs I’ve tried later.
All of this is just based in my own experience with the computers I have owned (2010 MBP, 2014 Mac mini) and the computers I’ve bought to later return because some flaw. Of course, if I had wanted to keep any of those machines I tried, I would have returned them and ordered a 16GB model. The reason I’ve always bought the 8GB machines, is because those were the only ones available in retail stores, easy to return.
As my rule of thumb, the newer the machine, the more RAM it uses. I don’t know if the Operating System version has something to do with it, but I clearly see a pattern, and nowadays I wouldn’t buy anything with less than 16GB of RAM.