More cards means more variety. More variety means more deck ideas. More deck ideas means more people battling in tournaments. More people battling in tournaments means the TCG is successful. That's the way it works.
Hmm I'll disagree with you on that point tbh.
Theoretically this idea works, but in the case of unlimited play where there are thousands of different cards, it doesn't. Which is what I believe DaVince is suggesting; he can't play due to the number of other cards.
When there is such a large choice of cards to make a deck from, some cards will be devalued due to the high competition and excessive power of other cards.
This is evident from unlimited tournaments, despite there being approximately 3000 different cards to choose from - competitive players will stick with some of the best such as Sneasel, Electabuzz, Blastoise and so on.
To stand a stronger chance of winning, many other players have little choice but also to play the most effective cards. As a result the majority of decks played in unlimited show very little variation. Because of this, unlimited play is very rarely used by Organized Play tournaments, as it is heavily biased towards a certain number of cards.
Therefore although there is greater range of picks, those which are used are often taken from a very shallow selection.
Cards which are good (such as Blaziken), however have poor chances and are rarely played.
The Modified format was introduced by WotC as a method of overcoming this problem. By reducing the number of cards that could be used, more decks could be played (saves getting beaten by the same archetype from 3years ago). So although the card pool is smaller, fewer sets have the greater effect on variety.
Less is More. Modified ftw :classic: