Being just "Xbox" is something I personally desired to see, kind of the "classy reboot," so to speak. I like that aspect of the name.
I'm not a fan of the "Series X" designator, though. I know it's trying to lift the current Xbox One scheme, and have "X" be sort of the premier experience they're aiming for, but it rings way too similarly to Xbox One X IMO. It's not confusing to me, I just think it's a bit redundant — and I think it does risk being kinda confusing to average consumers, but I think they can make up for that if the marketing and the actual hardware packaging hammers home the new monolithic silhouette to consumers — seeing the different form factor might make it plainly obvious that it's a new thing to people that might get confused with Xbox One X.