Having a mental lapse at the moment.
Looking to populate some form values (like Phone Country Code) based on other values that are entered into the form. I know it's possible to do inside a smart campaign, but is there any way to do this at the form level itself?
(Thread should be in Products.)
Absolutely. You can manipulate field values using the Forms API. And using JS for complex conditions is waaaay easier than SCs for the same task.