In the recent discussion post regarding the MTGA economy, Wotc gave a clear and authoritative position against dusting being introduced into the game: We never wanted players to feel pressured to dismantle their collection to build the deck they want, only later to be disappointed when they realize they need to reacquire cards they destroyed
Pokmon has also stated that an important theme of the Scarlet & Violet Series is comebacks, and that they plan to introduce Pokmon, Trainer cards, and Energy cards that can turn the tide of the battle. Because much about the Scarlet & Violet legendaries had not yet been revealed when this mechanic was revealed, the cards as originally-revealed concealed information, including their stage, type, and HP
Conveniently, the Ring's temptation means the Ring-bearer may draw and then discard a card when that creature attacks and some other Tales of Middle-earth cards such as the mighty Witch-King of Angmar also discard cards for their effects, giving Sauron more corpses to work with
Arachnogenesis Arachnogenesis is just a better defensive measure than Galadhrim Ambush unless you care about elves