Considering the look of the cuirass, I'd say pauldrons were merged with them, while greaves were merged likely with boots.
However, it's clear that this is to get more seamless looking armor than clippy as crap armor. Personally, mismatched clippy armor with next to impossible odds of completing a set until you've about worn out the character bothered the crap out of me.
Both, appears that the boots is up to the knees while the cuirass use a knee length skirt.
Two reasons, reduce clipping and allow for more unique armors. Both Oblivion and more Morrowind restricted armor design, Boots and gloves does not create this issues as the joint Is on limbs not on the bendable torso.
Cloth physic has two drawbacks, expensive as it had to be used on all npc, also mostly used on skirts, long hair and capes not full body cloth physic.
Luckily nobody here claimed it was done to make the game more accessible as lots of far more mainstream games like Runescape has more armor slots