Not only that if Magikarp and Wailord GX is defeated, the opponent gets to take away three prize cards
Many players would rather play a deck which has great matchups overall, than one which depends heavily on what you face
If you want a value-oriented mono-black commander, you have much better options, from Gonti, Lord of Luxury to K'rrik, Son of Yawgmoth
Strap in, theres a lot to learn and a load of places to cover
Of course, cards that do well competitively that are also incredibly rare tend to deliver a lot of value
The Scarlet and Violet era has introduced its own premium card treatments with the Special Illustration Rare format, which is different enough from the Galarian Gallery that the two do not directly compete for the same collector niche