Shouldn't Muslims be more entitled to supplicate for the betterment of humanity and the guidance of all people, following the example of their Prophet, peace and blessings be upon him, instead of limiting their supplications to Muslims only or cursing others?

The greatest contribution Muslims can offer humanity is presenting Islam beautifully and not neglecting to pray for the guidance of those who have gone astray, following the example of the Prophet (peace be upon him) who prayed for the guidance of disbelieving tribes.

It is not permissible to pray for mercy and forgiveness for disbelievers, due to the Almighty's saying: "It is not for the Prophet and those who have believed to ask forgiveness for the polytheists, even if they were relatives, after it has become clear to them that they are companions of Hellfire."

The prayers of Christians for humanity in general are not heard from them because they are directed to other than Allah. Their reality also belies their rituals and prayers, considering the hatred of their priests and rabbis towards Muslims.