How sound is the assertion that whoever experiences little success should persist in reading Surat Ash-Shams, so that Allah may grant them success wherever they turn, and that it contains many benefits, preservation, and acceptance from all people? And is this originally a Hadith?

There is no special virtue mentioned in the narrations for reciting or memorizing Surat Ash-Shams. Surat Ash-Shams begins with successive oaths from Allah Almighty by His magnificent creations, to emphasize that the purification of the soul is the cause of success, and its defilement is the cause of transgression and loss. The surah includes oaths by the sun, the moon, the day, the night, the sky and its builder, the earth and its expander, and the soul and its proportioner, clarifying the success of whoever purifies it and the failure of whoever corrupts it. Then it mentions the story of Thamud's denial of their prophet Salih and their hamstringing of the she-camel, whereupon Allah destroyed them with His punishment without fearing the consequence of that.