These values are actually exposed in the Shortcuts app, for example, if I fetch an Agenda Note** and then assign it to a variable:
…instead of assigning the entire note to the variable, you can now also select the Creation or Edited Date:
… resulting in the creation date that you can use to compare:
**) note that you can also go from the other end and use the Find Note to search on notes edited or created on a certain date as those are now searchable properties in the Find Note Shortcut, see