It's kinda funny to me since most duties have timers anyway, this one's just 30 minutes rather than an hour. Personally, it was one of my all-time favorite duties. It used the mechanics of the game to spell out a very different situation and really show the player desperation and danger. The first time you weakly flail at an enemy soldier only to realize you are in serious danger just made it all the more exciting. While 'stealth mechanics outside of stealth games' are almost never good (indeed, the tailing duties present in Endwalker show just what I mean) the simpler nature where you actually have to pay attention to aggro for once made it thrilling. The timer is just so that you don't wait 5 whole minutes for that minor regen buff to heal you and such. It adds useful tension.