I would never physically try to block someone from reclining with my hands. I would also not try to keep reclining if the person behind me felt strongly enough to physically block it. And I certainly wouldn't start recording while i was doing it.

The thing that should happen is he should politely request that she stays up because he feels like he needs the space, maybe hes claustrophobic. If she balks and says no i need to recline because of my back...grab an employee and ask is there another seat available to accommodate both of their requests. If there is not then I think the guy has to deal with his seat and he should not purchase seats in the back of the plane next time and that the lady should have the right to recline her seat if it reclines.