The difference hardly mattered to Lu Xuan. As he currently was, he didn't have the ability to fight for long, either.
That one punch alone had cost him 200,000 mid-tier spirit stones already.
All of his current powers were used for transforming his body to reach the Nirvana state. As such, every single attack he pulled at that moment had cost him all the mid-tier spirit stones that he had accumulated.
Even if he were to just maintain his current form at the Divine Transformation Realm and do nothing else, he would still have had to spend 500 mid-tier spirit stones every second.
As such, time was of the essence to him as well; he too lacked the ability to drag the fight out for long.
Both parties wanted to end the fight as quickly as possible. None of them wanted to drag the fight out longer than necessary.