These are proxy cards and not official tcg products
This means that aggressive decks with more than one colour can steeply benefit from lands like Starting Town, which will allow them to make powerful plays at the start of the game, no matter the colour of the card they're casting
Add in more Yarok, effects like Panharmonicon and you can double your doubling
While the Play Boosters are likely to be printed in some capacity until the set rotates out of Standard in 2028, the Collector Boosters end much sooner, typically after the initial printing run, which will have a huge impact on card value for the variants that can only be found in this product
For players who don't want to play combos, knowing what the combos are is still helpful for deckbuilding
When first joining the battlefield, Esper Sentinels power will likely be low enough for people not to bother about it