Yes FTLN that memory you linked is unbuffered, you can tell from the bottom bit of the spec list, when it says "Registered: No" this means unbuffered essentially.
I think the confusion from the point above is that Ryzen 3rd gen is Zen2, because Ryzen 2nd gen was Zen+, and so Zen3 will be Ryzen 4th gen. (Zen is arch, Ryzen is brand series). Then they also name their brand tiers Ryzen 3/5/7/9 to confuse things more.