Is Satan the ruler of this... world?
In in this verse 2889 κόσμου-(world) is used as of the people (worldly), not the earth.
"Now is the judgment of this world: now shall the prince of this world be cast out."-John 12:31 KJV
"νῦν κρίσις ἐστὶν τοῦ κόσμου τούτου νῦν ὁ ἄρχων τοῦ κόσμου τούτου ἐκβληθήσεται ἔξω·"-John 12:31 TR
Again in this verse 165 αἰών-(world) is used, as of the people (the worldly).
"In whom the god of this world hath blinded the minds of them which believe not, lest the light of the glorious gospel of Christ, who is the image of God, should shine unto them. "-2 Corinthians 4:4 KJV
"ἐν οἷς ὁ θεὸς τοῦ αἰῶνος τούτου ἐτύφλωσεν τὰ νοήματα τῶν ἀπίστων εἰς τὸ μὴ αὐγάσαι αὐτοῖς τὸν φωτισμὸν τοῦ εὐαγγελίου τῆς δόξης τοῦ Χριστοῦ ὅς ἐστιν εἰκὼν τοῦ θεοῦ"-2 Corinthians 4:4 TR
But Satan is not the ruler of the earth,
GOD is the only ruler of "Heaven and Earth" 1093 γῆ-(earth) as in
"At that time Jesus answered and said, I thank thee, O Father, Lord of heaven and earth, because thou hast hid these things from the wise and prudent, and hast revealed them unto babes."- Matthew 11:25 KJV
Ἐν ἐκείνῳ τῷ καιρῷ ἀποκριθεὶς ὁ Ἰησοῦς εἶπεν Ἐξομολογοῦμαί σοι πάτερ κύριε τοῦ οὐρανοῦ καὶ τῆς γῆς ὅτι απέκρυψας ταῦτα ἀπὸ σοφῶν καὶ συνετῶν καὶ ἀπεκάλυψας αὐτὰ νηπίοις·"-Matthew 11:25 TR