Wha..? I'm totally not following, iCloud syncing is completely transparent and built-in to 1Password. There's 0 extra work to support it (outside of finding how to turn it on, because it's buried in the UI), there's literally less work than 1Password's own subscription service, because that requires setting up an account whereas iCloud doesn't.

You can use iCloud without an account? Is iCloud available outside of Apple ecosystem? Otherwise it doesn't seem very relevant since its not a general solution.

Yes, you're right, this only works for Apple devices, so going cross-ecosystem is definitely a benefit of their subscription service! I disagree on that meaning it's the iCloud solution is irrelevant though, skipping the $36/a year, and the additional control over your data not being on a subscription entails, seem like relevant benefits for the people who fit those requirements!