The text was written for humans, using human language. Even if it is the inspired word of God, why would I imagine "days" really means thousands of years? It is far more likely that the author believed the end would be very soon, and was wrong.Only if you’re thinking like a human. God doesn’t. He’s not bound by earth time, like we are.
8 “For my thoughts are not your thoughts, neither are your ways my ways, saith the Lord.
9 “For as the heavens are higher than the earth, so are my ways higher than your ways, and my thoughts than your thoughts.”
People thought Christ’s first visit to earth was imminent, for a long long time. By earth years, it was a long time. By universal (God’s) time, it wasn’t.