True, but it was definitely broken by the time the landing burn commenced. So it's hard to see where it failed. I think the other fins must have done much better, otherwise it would have totally lost control. The telemetry did get weird at one point, but it's hard to say if that was just an error in the data or actually happening.

Note that besides the fins they added more cold gas thrusters this time, so a loss of one or more fins wouldn't mean loss of control like with the previous attempt.

I also think the connection between the fin and the inside didn't fail and held up well. I remember from Space Shuttle that a small defect in the heatshield meant a stream of superheated air blasted in like a plasma cutter and destroyed the insides, even in parts where the heat shield was just fine. But with this flight on Starship it seamed like the fin burned away, but the inside was fine, otherwise I think it would have blown up. It even seamed like the fin moves after a lot of it was burned up, so that would mean the motors and control systems were still working. But I'm still not sure at what point it failed, some of the movement could be due to atmosphere with it hitting the end stops, so it looked like a controlled movement to a certain point.

Very interesting and cool nonetheless.

Edit: Just rewatched and you can see at 1:04:22 it makes a move which is very fast. At this point I feel it's broken and every movement we see is due to the thing shaking around in the atmosphere. But somehow with the thrusters and other fins that may have faired better it maintains control. It really was the little Starship that could.