That card came out before the big boom in popularity that led to the oversaturation of the market. Likewise, Shohei and Trout rookie cards fetch a pretty Penny now as they debuted when the industry was down and less cards were made. As others pointed out, the inclusion of numbered cards now adds a new element where they should retain value and even increase. But even now with how many releases there are there are so many 1/1s kicking around too.