Perhaps it's me but the calculation from the article above seems pretty clear.
Each of the two main-gear legs on the 777-300ER supports 46% of the aircraft’s weight and this is spread between six wheels. The 777-300ER has an all-up mass of 352t.
In contrast the Boeing 747-400ER, while having an all-up mass of 414t, carries its weight on four main-gear legs each supporting 23% of the aircraft’s weight. Each main-gear bogie has four wheels.
This means that the 777-300ER, despite being the lighter of the two, potentially concentrates a greater load on each individual wheel.
This data means 27 tonnes per wheel for the 777-300ER but only 23.8 tonnes for the 747-400ER.