Currently, the way to check if a time has passed is by doing:
LT(Time("2021-02-14T01:56:04.939970Z"), Now())
There should be a built-in function isPast that can accept an iso date string, it should return true if the given date is a past date, false if otherwise.
isPast("2021-02-14T01:56:04.939970Z") // true