Soft-activated users are the ones that completed their initial onboarding phase and made their first significant action(s). They have been activated but they're still in an exploration mindset.
Hard-activated users are the ones that passed a certain tipping point in terms of their product usage and the value they gained from it. They trust the product and are ready to adopt it.
Link to full post:
https://www.mobilespoon.net/2021/01/difference-between-soft-activated-and-hard-activated-users.html