It's almost like they decided to hack their own game engine to stop unwanted effects that resulted from it in their world design, and in doing so broke another a more core aspect of the game's ability to function...
Putting arbitrary limits on what a player can and cannot pick up, outside of their actual encumbrance limits, just to prevent other system breaks stemming from poor engine design was a ridiculous call...
((For detail: you can automatically pick up and throw enemies and objects because of the way the engine works. Rather than fix the engine, their solution was to put a limit on what weight of things players could pick up or throw independent of the core rules and outside it or the encumbrance and carry-weight system. This now means that players can't pick up and carry items they should be able to - such as a heavy set of armour. They can carry up to 300 lbs of goods, and can happily do so, as long as those 300lb are in discrete 20lb packages... but they can't pick up one object that weighs 40lb, ever. What a system. Incidentally, wearing armour that you do not meet the strength requirement for reduces your speed by 10 feet - that's literally all it does. It does not inhibit you or give you and disadvantages, or anything at all, it just reduces your speed. Unless you're a dwarf, in which case it doesn't even do that.))