Well, First Edition Charizard is now sold for $10,000 and more on different online sites
However, it requires you to have "Uxie" and "Azelf" on the Bench at the same time and burns off all of the attached Energy, making it not only very difficult to set up but also makes "Mesprit" extremely vulnerable even if it one shots a Pokmon ex
The original Base Set introduced 102 cards, including the now-legendary holographic Charizard that has become synonymous with valuable Pokemon cards
It's one of the reasons milling isn't as strong, it takes longer to kill someone, and they are likely strengthened by it
For many collectors and people who just want to get into the game, that wont matter much
In fact, this card is so efficient its currently run in some top-tier Pioneer Izzet decks