That's because when you put too many ingridients in a pot the recipe gets ruined. Expanded for Pokemon TCG reflected that as it mimicked yugioh. When the card pool is too large and there's too many things to account for skill is going to take a hit no matter what. Yugioh kept making new cards more and more powerful to sell to competitive players but without a rotation that creates a mess to where the game is today. For pokemon my main problem is the major imbalance between rule box pokemon and regular pokemon still having around the same HP as from 15 years ago. However, the gameplay is still similar. For modern yugioh though the problems are too many to list it's no surprise the game has a very difficult time keeping new players invested into the game.