This rule was clearly added to prevent players from gaining too much advantage in having more resources in hand than the other players, and so this rule can often be seen as a downside since you are losing cards due to a simple yet sometimes unavoidable rule
With so few available, it makes sense that a 9.5 gem mint copy fetched $14,000 on the auction site Fanatics Collect in 2023
This will also turn your dorks into an Ancient Greenwarden and play lands from your graveyard, Carnage Tyrant to make it a beater, Grunn, the Lonely King to double its power when it swings alone, Kamahl, Fist of Krosa to Overrun and make lands dorks, Multani, Maro-Sorcerer to grow massively in size and get shroud, Nemata, Grove Guardian to make a bunch of tokens, Primordial Sage and Soul of the Harvest to draw cards, Rampaging Baloths to landfall and game win, and that's just one casting cost
Some are too expensive (Vampiric Dragon) and others are too low-impact (Avacyns Judgment)