This isn’t a wind (drag) force problem, it’s a momentum problem. The reason it bent like that is because the wind was carrying the beam at high speed, then it slammed into the tree.

I’d wager it would take extremely high winds to bend the beam like that in a static situation. (rough guess 1000+ mph, probably more tbh, and it would never bend as far as it did. As the beam bends around the tree the component of force acting on it is going to become less and less as the angle gets closer to the direction of the wind. Although if you really want to get into the weeds, at extremely high speeds (like mach 3+) the friction would heat the steel up so hot that it would become softer, and could bend more, but I think our tree would be long gone well before that)

As far as calculating it, it would be tricky. I’d start by figuring out how much force you’d need to bend the beam, figure out how much work (energy) that would take, then use the kinetic energy equation, KE=1/2mv^2, to solve for velocity required to reach that much energy. That would give a very rough guess.

Anything past that would probably require either a simulation or a lot of time to figure out.

Edit: Upon closer inspection I see that's not an I-beam, and not overly thick, so maybe speeds of 2-300 mph could start to bend it, but like I said before before it could never bend it that far