I recall how you also failed to grasp that a wheel spacer of a certain size was physically impossible to be made hub centric!

Right, I would suggest you first look at exactly what the OP has posted.

-The pin in the centre of the Ford rubber mount is a fixed length, the top of it butts to the captured nut in the chassis, the base of it butts to the lower plate. That exact length means the plate then bolts exactly parallel to the chassis and so does the beam. The large bolt then simply keeps that in place under the correct torque and the rubber fills the gap totally.

-The pin of the solid beam mount the OP has is quite a lot shorter, so given that the two bolts at the front of the plate that attach to the chassis cannot move, the only thing that can take up the slack formed by the shorter solid mount is the big bolt. In doing so it raises/bends the plate in an arc relative to the two bolts on the chassis plate, rather than directly upwards, placing side loading into that bolt, not just torque.

-If yours/others solid beam mounts also have a shorter pin than the Ford rubber ones, then yours is doing the same, however if the pin on yours is the same length as the Ford rubber ones then the gap above it cannot be reduced and the top of the mount wont sit on both the chassis and the plate at the same time, hence the big gap remains.

-However if your solid mounts have a pin the same length as the Ford rubber ones and your mounts are the same thickness as the Ford rubber ones then it will mount correctly. The pictures suggest thought that is not the case.

-The OP and others are not stating that all solid mounts are shorter than they should be, just the ones in question here.

Now I cannot make it simpler than that!

I had the same issue years ago with some poly beam mounts which were thinner than the Ford rubber one and used a shorter pin, as soon as I realised what was happening then in the bin they went and they were replaced by new correct Ford ones. The poly ones were so much thinner that the big bolt was actually running out of thread and the captured nut was starting to strip its thread as a result whilst a gap still remained. I imagine that is why so many people end up knackering those captured nuts in the chassis doing the same thing.