There were many rich nobles and rich families – and many of them were richer than the royal family, but the reason they held power was a simple one: they controlled the military, the adventurers, and the mage hunters.
Matheson originally thought he was superior to the common man, as he chased after wealth, thinking it was a measure of power, but as he himself got stronger he was beginning to realise one thing: In the face of pure power, wealth is like a paper shield, an illusion of superiority.
As he got stronger, he realised how weak he truly was.