Mira didn't even stand a chance against such a powerful strike. No, to be more accurate, there were probably only a handful of people in the entire Mortal Cultivation World that could survive the final strike of the Heavenly Punishment Tribulation.
That's the terror of Heavenly Tribulations, especially a Heavenly Punishment Tribulation.
The entire reason for there being a Heavenly Punishment Tribulation is to kill those who are attempting to break 'Heaven's Rules'. Although the Heavens have to play by their own rules as well, many of those rules no longer apply once the Heavenly Punishment Tribulation is activated.
Not only that, but the Heavens aren't dumb. Although the Heavens don't exactly have emotions, they are able to sense how dangerous and troublesome someone is.