Hubitat version 220.127.116.11. Comparing two DateTime variables in RM 5.1 appears to only compare the Time component, not the Date. This results in comparisons that should pass (e.g 5 pm yesterday < than 2 pm today) failing - a dateTime from yesterday compares as greater than a dateTime from today.
Here is a sample rule:
In this case the trigger hasn't fired in a while, so variable NextPoll is from yesterday, 9:40PM on 12-27 is comparing as greater than 9:37 PM on 12-28:
the condition is still false.
Logging shows the problem:
Aside: The mental model here being used is the traditional one of "datetime" type being a point on the timeline from past to future. These can be compared as less or greater than, subtracted to create a duration, etc.