Its odd that in the video that you couldn’t see a missile trail or explosions of AA artillery or tracer fire. I suspect that this jet may have just lost it engine when it went down. It looks like a video I’ve seen of an F-14 about to go supersonic when one of its engines had a catistrophic failure.
Could be.
Also if enough residents of a city are armed they can put up a pretty thick small arms barrage at a low altitude.