In the late 70’s, I was a KC-135 co-pilot when every flight crew member on the base was suddenly ordered into an auditorium on the base. No one else allowed; mandatory attendance. Really hush-hush.
Once we’re all there wondering what the hell was going on, out comes the Colonel to introduce a speaker.....Belenko.
Fascinating, to say the least. We all learned a LOT.
The point is that the Russians are probably not being truthful as to the capabilities of this aircraft.