Who are those Mentioned in Sura 1:7?

Just to clear up this issue once and for all, I present three classical Sunni Muslim commentators who make it absolutely clear that Sura 1:7 is a reference to the Jews and Christians:

This is why they were led astray. We should also mention that both the Christians and the Jews have earned the anger and are led astray, but the anger is one of the attributes more particular of the Jews Allah said about the Jews, (Those (Jews) who incurred the curse of Allah and His wrath) (5:60). The attribute that the Christians deserve most is that of being led astray, just as Allah said about them, (Who went astray before and who misled many, and strayed (themselves) from the right path) (5:77). (Tafsir Ibn Kathir. Commentary on Sura 1:7.)

(The path of those whom Thou hast favoured), the Religion of those whom You have blessed with the Religion and who are the followers of Moses, before the blessings of Allah deserted them, in that He shaded them with a white cloud and sent down on them honey and quails when they were in the wilderness. It is also said that (the path of those whom Thou hast favoured) refers to the prophets. (Not of those who earn Thine anger), not the religion of the Jews who earned Your anger, whom You forsook and whose hearts You did not protect until they became complaisant. (Nor of those who go astray), nor the religion of the Christians who erred from Islam. Amen: thus shall be its custodians; it is also said that Amen means let it be so. It is also said that it means: O our Lord! Do with us as we have requested You. And Allah knows best'. (Tafsir Ibn Abbas. Commentary on Sura 1:7.)

the path of those whom You have favoured, with guidance (from alladhīna together with its relative clause is substituted by [ghayri l-maghdūbi ‘alayhim]) not [the path] of those against whom there is wrath, namely, the Jews, and nor of those who are astray, namely, the Christians. The subtle meaning implied by this substitution is that the guided ones are neither the Jews nor the Christians. But God knows best what is right, and to Him is the Return and the [final] Resort. May God bless our lord Muhammad (s), his Family and Companions and grant them everlasting peace. Sufficient is God for us; an excellent Guardian is He. There is no power and no strength save in God, the High, the Tremendous. (Tafsir Al Jalalayn. Commentary on Sura 1:7.)