all of this is self-evident within the religion of Islam.
So how can anyone say that it was never stated that he was sent to anyone but the Arabs alone, when his very preaching, his emissaries, and his military engagement extended to the Jews, the Christians, and the Zoroastrians after the polytheists—and when this, peace and blessings be upon him, is precisely how his biography treats them?

Furthermore, the text that reached us through continuous, mass transmission from him—the Quran—mentions in a great many passages his summons to the People of the Scripture to believe in him. Indeed, in it Allah, Blessed and Exalted, declares the unbelief of those Jews and Christians who rejected faith, and He commands that they be fought, as in His saying:

“Those who say, ‘Allah is the Messiah, son of Mary,’ have certainly disbelieved. Say, ‘Who could prevent Allah, if He wished, from destroying the Messiah, son of Mary, together with his mother and everyone on earth? To Allah belongs the dominion of the heavens and the earth and all that lies between them; He creates whatever He wills, and Allah is competent over all things.’” ⦗Al-Māʾidah 17⦘

And in the same surah He also says:

“Those who say, ‘Allah is the Messiah, son of Mary,’ have certainly disbelieved. Yet the Messiah said, ‘Children of Israel, worship Allah, my Lord and your Lord. Whoever associates partners with Allah, Allah has forbidden him Paradise, and his refuge shall be the Fire; the wrongdoers will have no helpers.’
Those who say, ‘Allah is one of a trinity,’ have certainly disbelieved; there is no god except the One God. If they do not desist from what they say, a painful punishment will befall the disbelievers among them.
Will they not turn to Allah in repentance and seek His forgiveness? Allah is All-Forgiving, Most Merciful.
The Messiah, son of Mary, was only a messenger; messengers passed away before him. His mother was a woman of truth; they both ate food. See how We make the signs clear to them; then see how they are deluded!
Say, ‘Do you worship, instead of Allah, that which can neither harm you nor benefit you? Allah is the All-Hearing, the All-Knowing.’
Say, ‘People of the Scripture, do not go to extremes in your religion beyond the truth, and do not follow the whims of a people who went astray before, led many others astray, and strayed far from the right path.’” ⦗Al-Māʾidah 72–77⦘