For my upgrade, due to having lesser vulnerabilities, I decided this year (after 20 years of only using Intel) to go with AMD. Had my doubts, but this article made me decide it's time to go AMD route.
Unfortunately, AMD has PSP. [1] ARM has TrustZone. [2] You'd have to get a system with a POWER9 [3] chip, such as the Talos II from Raptor. [4] That has quite a price tag though, on account of not being mainstream.
It should be noted that ME and PSP are both (a) a technology to implement a super-root over your entire system and (b) an implementation of said super-root environment that you do not control and cannot out out of. Trust Zone is only (a). Trust zone just defines a technology that may be used to implement such a thing, but it itself is harmless and does not actually do anything.
There are chips you can buy that do not come with any TrustZone code, and you may write your own to put in there, if you so wish
Thank you for these links, I'll look into them. And yeah, I do plan my upgrade to be quite expensive. For me, the work horse, has to be a beast to support virtualization, gaming and quite some editing - so in the end the price tag is not my main criteria.