Basically, the deck feels unbalanced, and if players know your strategy is basically to go all in on creatures, they're going to be far more aware of your combos and keen to stop them
A foil 1st edition Charizard (sold for $369,000 in December) is trading on the power of the Pokemon brand, a nugget of nostalgia which makes easy headlines because it naturally appeals to millions who grew up with a Gameboy
Theres also the fact that this green sorcery only costs two mana
The tricky thing is that formats regularly remove cards from Standard every few years, typically in the Fall
As time passes it is slowly fading away from relevance, but it is our format's annoying burden to bear for the time being
Remember, deck construction rules wouldn't officially happen until Wizards started up the DCI in January of 1994