I already play on PS4 EU and NA with over 1k cp on each.
I just feel like I am way in the back of the bus with all the add-ons available to PC
If I tried to start playing PC, would this computer make it enjoyable, or not-so-much?
As a starting point, here are the minimum requirements for playing ESO on Mac. While your Mac meets these requirements, playing on an integrated GPU will restrict the performance that you can get in ESO.
Mac Minimum System Requirements:
Operating System: macOS High Sierra v 10.13
Model: Late-2013 27-inch iMac and Newer
Hard Disk Space: 85 GB free HDD space
Internet: Internet Broadband Connection
From CPU, disk speed and RAM pov you will be fine. However I would advice you to get some eGPU. You can put one yourself (there are Thunderbolt 3 eGPU cases) but what you need to remember is that only AMD provides drivers for macOS.