It seems highly likely that other planets hold life. Some with just animals, and others with intelligent life. Some of these planets may have had intelligent life that both had remained faithful and some that had sinned, hence, why the angels knew good and evil.

"Then the LORD God said, “Behold, the man has become like one of us in knowing good and evil." Gen 3:22

I assume the devil likely chose Earth to deceive intelligent life because Earth was special to God. Through jealousy and pride, the liar decided to attack a favored relationship between God and Adam.

"And they heard the sound of the LORD God walking in the garden in the cool of the day." Gen 3:8