In short
Jesus does not dispute whether Satan can indeed offer the kingdoms of the world (Matthew 4:10), because the Gentiles did indeed serve the devil, but God yet demanded their exclusive worship.
In his reply to the devil (Matthew 4:10) Jesus does not deny that the devil has a certain degree of power in this world. Therefore Jesus does not reject the offer as laughable and presumptuous. It may be granted that all Gentile nations of the world had been smothered in the service of the devil, but the Lord God demands that everyone without distinction worships and serves him alone.1
10 Then Jesus said to him, “Be gone, Satan! For it is written, “‘You shall worship the Lord your God and him only shall you serve.’”