The OP notes that they can infer a 7B model at 2s/tok using their CPU setup. Equivalent inference on a 4090 ($1600) is up to 400 tok/s, or 0.0025 s/tok. This is an 800x difference.
(to be fair, you can do better than the OP's performance, but we _are_ talking several magnitudes of performance, not to mention energy efficiency, which matters at scale)