NOTAM 2/9510 says, in part:
They’re discussing this over at
https://www.reddit.com/r/flying/comments/t4smet/notam_29510_and_russianamericans/
They are specifically wondering if Russian citizens legally in the United States are grounded from general aviation activities. The discussion is focusing on being a CFI or a student if you are a Russian citizen (ETA: Or even simply being a passenger on a regular scheduled commercial domestic airline flight).
I happen to know one such person (a CFI / ASEL in the S. F. area), who just yesterday had occasion to send me an e-mail including this comment:
There’s a slim chance that ban-all-russians NOTAM precludes me from teaching, I’ll let you know if that frees my weekend up!