You are right. I just got 4 of the 2012 for $100 total last weekend. Super easy to upgrade the memory to 8GB or 16GB. A bunch of screws to remove to upgrade the HDD to an SSD. Big performance difference and High Sierra or Catalina is very useable. I also got a 2014 MM and I think it got a bad rap because they removed the thumb openings, the CPU seem like a downgrade and major work to get the HDD out to swap for an SSD. A hack I found is that for the Hybrid drive version you can just swap out to a high capacity SSD using an adapter. And the non-hybrid just buy one of those NVME adapter that just stick near the fan. I do want the 2018 and 2020 just to play with but bad that they made it not user upgradable.
