I guess the high-end iMacs and iMac Pros (remember the iMac Pro? 10 core Xeons upgradable to 512 GB of RAM!) just never sold very well, so they canned the idea

I guess the high-end iMacs and iMac Pros (remember the iMac Pro? 10 core Xeons upgradable to 512 GB of RAM!) just never sold very well, so they canned the idea of selling iMacs to pro users and instead chose to focus on the lower-end market that was previously served by the 21.5". So it seems to me like the iMac has very much been repositioned as a stylish, basic desktop computer for the home and general office tasks now. No M3 Pro/Max, no bigger monitors, limited I/O, etc. I personally don't really like it because I have labs full of decked-out 27" iMacs that are now kind of left without a clear upgrade path, but I understand what they're doing.