I'm not you, but as you are already planning to replace a 3000 Zen within a year with another one, I would look at the 3700 or 3700X to be honest, maybe even the 3600 and put those savings into the 3950 or a better PCIe4 NvME SSD that will maybe be announced and released before the end of the year. At some point, the difference between those cores and clocks--and it looks like the non-X versions and especially that 3600 have that magic Zen boost ability to more or less match their more expensive X-brethren--is going to be negligible on your server/backup/whatever ITX that you have planned. And with that small case and limited cooling even with the AIO on what will be some pretty hot chips under boost, you probably want to go with efficiency, all the while saving money, and I mean really: is that 1-2% difference going to matter in the end?
Don't answer that. 😀