Probably due to there are more S10 & S10+ users and they started working on the beta soon after those phones were released. Not 10 was just released about 2 months ago. Hopefully we'll get it soon.
According to some articles Beta for Note lineup will not be out until end of month. Samsung delayed it again due to some issues. I hope those articles are wrong but don't hold your breath for Beta.
Lol, well I ain't trying too bust any body bubbles.. but honey I had gotten the One UI 2.0 beta on Oct 28th 2019 on the Samsung Member app and mane I definitely loving it. 🤗🤗