I live in Germany and have both german and russian citizenship.
The relations between the U.S. and Russia are not very good.
Will my russian citizenship hurt admissions for MIT?
Should I cancel it before I apply just in case?
As opposed to your German citizenship? No. Your admissions chances are hurt by virtue of having any foreign citizenship, but your Russian citizenship will not be more detrimental.
No. It would not matter a whit other than in terms of quotas. I have no idea where Russians are in terms of being under or over represented in student visas
(and the reason isn’t hostility to international students- it’s due to most US universities holding international student populations somewhere between 8-15% of enrolled undergraduates. This has been true for many years, not just in today’s political climate)
MIT’s international application acceptance rate is about 3%, less than half of the overall rate. So being International makes it difficult, but I don’t see data saying Russia is worse than anywhere else.