There is no more sowjetunion. And it is a bit frustrating, that we are in a new cold war right now, because people were too lazy(on both sides) to adjust after the wall came down. So yes, russia is an enemy again, hurey and sure it makes not much sense letting them gather direct data to boosten their air defence missiles. But this works in both ways, no? If you have the S400 - you can study extensivly its weaknessess.
Apart from that, china seems a bigger threat.