Demand for Chicago office space kept falling in 2023, a sign that a true recovery for downtown could be years away. The drop-off comes even as some high-flying cities like New York City saw demand nearly return to 2019 levels, while tech-heavy markets on the West Coast remain stuck in the doldrums far behind Chicago, according to a new study by VTS, a New York-based software firm that tracks the number of companies checking out potential new office space. “Being in the middle of the pack is what we expected from Chicago,” said Max Saia, vice president of investor research for VTS. New York bui…