who are the current descendants of the Sumerians,ancient Egyptians and Phoenicians?

[Kenshiro]

Of the ancient Phoenicians i suppose they could be the Lebanese

[KirillMazur]

A minute of conspiracy.
Upper class:).
https://i.postimg.cc/bvs5Vh4F/image.jpg
Who is heir of the plain folks - I do not know, but in some of the Western Europeans this component should be present too according to this logic.
Plus, the concept of "article" in Indo-European languages does not appear without a reason (West have, East haven't).

[Zagrosian]

Phoenicians would be primarily the Lebanese - the Christian ones in particular - but they were all over the Mediterranean coast.

Ancient Egyptians: Modern Egyptians. Particularly Coptic Christians although the Muslim peasantry(fellah) are certainly indigenous to the area too.

Sumerians: Depends on what you define as Sumerians. Are Akkadians Sumerian? Or do you only refer to the original, non-Semitic people who got invaded by Semites and the mysterious Gutians? It is estimated that the southern Mesopotamian population was reduced by 60% after the Ur III dynasty, mostly due to soil salinity, which would explain their sudden demise of Sumer and the Sumerian language and the rise of Semitic dynasties in central and northern Mesopotamia. Damages to the irrigation infrastructure thousands of years later also had a tremendous impact demographically. Modern south Iraqi Muslims look very Arabian shifted, and there is also a heavy Iranian and SSA admixture which is not exclusive to Afro-Iraqis. The Mandeans of south Iraq and Khuzestan on the other hand are surprisingly similar to Assyrians of north Mesopotamia and very distant from Khuzestani Lurs/Persians and Arab Muslims. I'm sure descendants of Sumerians can be found in all the mentioned groups.