I think this is more metal fatigue due to time and use. This happens pretty routinely to metal handled shop brooms in my experience. I have done this with 2 or 3 of them.
In the normal use of these brooms you apply pressure from opposite directions constantly. This back and forth pressure eventually fatigues the metal.
Wooden handled ones tend to last longer.
Yellow leaves on the bottom of the plant is the most common sign of nitrogen deficiency.
This can be caused by lack of nitrogn availability or other things limiting the uptake of nitrogen into the plant.
Overwatering: too much water can create anaerobic conditions (No oxygen). Bacteria in the soil convert ammonia and nitrate to N2 gas.
Any disease effecting the root. This includes fungal and bacterial root rots. Letting the pot dry outcan help reduce the pressure.
Other species that feed on the roots. Fungus gnats, nematodes, and many more things can feed on the roots.