Interesting. For what its worth I've also been trying out various Linux distros on an old Mac - in my case a 2009 MacBook Pro.
The following had various significant issues with the hardware: ChromeOS Flex, Elementary OS, Pop!_OS
The following ran fine without any tweaking: Linux Mint Mate, Linux Mint Xfce, Zorin OS, Ubuntu LTS.
Of these, I've settled on Linux Mint Mate or Xfce (yet to decide which one)
Linux Mint Cinnamon was generally fine (and I prefer the interface to Mate and Xfce) but had an issue whereby it would not consistently suspend when closing the lid (issue was also present in Ubuntu Cinnamon). Could probably live with the issue but decided to go with one of the other Linux Mint editions.
There is the OS (Linux Mint, Ubuntu Budgie, etc), and there is the Desktop Environment.
Generally the OS will govern what hardware will work, and what software you can install.
The DE will govern how easy it is to use that OS, and how well things perform.
For example, the Mate and Xfce DEs tend to give you the most snappy response, but Mate is generally easier to use.
I have been struggling to find a system that works on my new Raspberry Pi 5 and lets me do everything I want.
I have settled on Ubuntu Budgie as the OS, as it lets me use Bluetooth and run MEGAsync for cloud storage. However, it is rather slow and uses lots of CPU so I installed the Mate DE on top of the Budgie OS.
Brilliant! Everything worked, and worked brilliantly quickly.
So, for me, the Ubuntu Budgie OS, with the Mate Desktop environment, is the optimal set up for one particular computer - the Raspberry Pi 5.
Alternatively, for my late 2015 iMac, I find that the Linux Mint OS, with the Cinnamon DE, is most useful.