This is a beloved mechanic for good reason: it draws cards, incentivizes attacking, and adds a fun and simple mini-game to the larger game of Commander
If a permanent that's already on the battlefield without time counters on it becomes a copy of a permanent with vanishing, it will stay on the battlefield indefinitely (unless time counters are somehow put on it later)
Disney has had a lot of failures in the game space, and even though this is very different in nature from something like Disney Infinity, the outcome could have been the same
Absolute Virtue Adelbert Steiner Aerith Gainsborough Ambrosia Whiteheart Ardyn, the Usurper Ashe, Princess of Dalmasca Bahamut, Warden of Light Balthier and Fran Barret Wallace Bartz and Boko Beatrix, Loyal General Black Waltz No
Big green decks want spells that help enable devotion, not a couple of 3/3s
If you fog the damage that would be dealt by creatures with toxic or infect, they wont deal damage, which means no poison counters