I agree that global decentralization is ideal but not a must, as far as I’m aware Z-cash is just as decentralized as Monero, & Bitcoin. I have used Z-cash, & so far haven’t had any noticeable issues. It’s not my preferred currency but it is one that I would utilize if needed. I used Z-cash when it was worse back in the ~20%+ dev tax days, etc., & gave Zooko my thoughts, & feedback, & it looks like he implemented most of it. Z-cash used to be way worse back then, not saying it’s perfect but it’s made a lot of improvements.