In this case, it dies before the activated ability that would regenerate it resolves
Notably, this Selesnya Dino legend can be cheated into play as early as turn one(!) with the three-mana planeswalker Sorin, Imperious Bloodlords -3 ability, because in addition to being a Dino, its also a Vampire
All of the circled abilities are considered to be printed on the card
(9/20/2024) If a creature with a survival ability isn't tapped when your second main phase begins, the ability won't trigger at all
Its likely to stay banned in Commander for those reasons, Id say, even though Ive argued its worth a shot at an unban given whats happened and how much better players are at the game and Commander politics since Prophet of Kruphixs printing
The moon waxes, full and gibbous above Innistrad