The question about the price difference between downtown donruss and donruss optic

Hello everyone,I'm a NFL fan from Taiwan where almost nobody watches the NFL games. I recently started collecting the downtown card on Ebay , and I got a PSA9 2023 Njigba donruss optic downtown for usd700.

I checked the price guide on Ebay, same as PSA9 grading, the card in donruss optic is nearly 700, and in donruss is nearly 670. It seemed that the price between donruss optic and donruss is not much difference.

I wonder is this normal ? Because from my understanding, donruss optic cards should be much more expensive and rare. Thx