Eh, that was the working assumption up until very recently. With the advent of drones and pin point artillery, having a lot of infantry support just means the enemy kills a tank and a platoon.
The Russians have just been avoiding sending tanks into urban settings by leveling entire cities. I think this particular conflict is going to be rewriting a lot of doctrine we have about combined arms warfare.
My historian friend shared a quote with me whose source I don't recall, but it was roughly "wars are fought based on the rules written during the previous war". He thought it was not always true, but interesting to look at the ways in which it was (i.e. considering how military strategy evolved at the beginning of WW2)
Eh, I think you can definitely break a track or drivewheel with this. If your tank looks like the one in the image, you might even do a little more damage.
It's also a great way to scatter yourself over a wide area by means of high explosive.
Humans become dangerously inventive and resourceful in guerilla warfare. Its fun (and sometimes horrifying) reading old booby trap recipes that was shared around by Milorg here in Norway during WW2.
Track impact - mobility kill by damaging roadwheels and/or track, or just getting stuck there
Direct side impact - probably nothing
Random gear impact - even old tanks have external mounted machine guns, optics, radio antennae, and shit that could be disabled
Exposed crew impact - squishy squishy
Of all these possibilities, I think just trying to get the damn thing stuck in the wheels/tracks is the most likely to actually work, even on relatively modern tanks.
A steel beam weights 10 to 100 kg per meter, railway rail is 40 kg/meter, so I'll take 50 kg. Four story building in Europe is approximately 12m.
In the drawing, beam+timber are almost as long as the building is tall, so for simplicity we can assume 11m, of which 5m is the beam and 6m is the timber, and we can assume the pendulum being suspended at 1m above ground in resting position. Beam's centre of mass is located at half it's length, so 8.5m is our effective length. Angle at which the beam-timber are standing looks like, dk, 35°? Then, the beam is suspended ~5m above ground. A 250 kg beam would have potential energy of 12.5 kJ (close to .50 cal). Alternatively, I can guestimate a 100° swing arc and 32 kJ energy, which is slightly more than muzzle energy of 14.5mm anti tank rifle. With panzers 3 or 4 we're looking at something like 15-20mm side armour, 14.5mm B-32 bullet (steel core) could pen 32mm at range, probably closer to 40+? point-blank. Of course, a bullet concentrates this force on a small area, through an I beam could also hit with a corner, give or take bigger kinetic energy of the beam and the need to puncture (absolute best case scenario, ofc) 15mm instead of 40+, and the fact that the bullet doesn't expend all energy purely during pen, so required energy for penetration is even lower. Another interesting moment in considering impact to and near hatches, welds, riveted joints, etc, is that unlike a bullet, which penetrates and carries a significant portion of it's kinetic energy inside - even a steel beam which initially punctured the armour with it's corner would still get stuck and transfer all its energy to whichever it hit.
In conclusion, with an older/lighter WW2 tank the beam under optimal conditions could maybe perforate the armour, break some welds, or at least dent it. And if we're talking about a less armoured vehicle, like an APC or an armoured car- the beam can either go through or significantly bend the ppate, likely disabling the vehicle. Could even work against IFVs (BMPs are cardboard, there are areas on the side which can be penned with small arms), through it's hard to imagine how it would be worth the hassle in modern context. And in any case crew would get disorientated by their whole world turning into a bell.
Many early tanks were designed to deflect small arms fire and shrapnel from artillery.
Even so: Aas anti tank weaponry and armor to match developed: tanks notoriously had weak armor when not being hit directly from the front. A swinging I-beam from an upwards sideways angle could definitely compromise a 1930s era tank in a critical fashion.
