Exactly what has been said, this is a public beta and not the general release. It has been posted here and on Discord that Phone(2) & other devices will be receive the update from in December. So, you device will get Android 15 (if you want it) 3 months from when Android 15 was brought to Pixel… this is very good and should be celebrated.
I’d also recommend you submit you feedback re; N-Dot to the software team via settings>system>feedback.