I am on iOS 16.1.1 and 1Password 8 and I have been to several websites where on checkout it would display some credit card choices from 1Password 7 to autofill.
Now that prompt never happens. I have tried turning on and off 1Password from the iOS Password settings, Allow Filling From... option
The sites I have tried recently were Williams-Sonoma, Walmart, and Lowes. It seems to have been broken in 1Password8, but don't have 1Password 7 installed any more to test.