If 1Blocker extensions appear greyed out in iOS Settings > Safari > Extensions, please check if your iPhone has any Screen Time restrictions enabled.
Here's how to do it:
Go to Settings > Screen Time > Content & Privacy Restrictions (enter your passcode if required).
Scroll down to the Content Restrictions section.
In Content Restrictions, go to Web Content. You'll need to set it to Unrestricted Access to activate 1Blocker. Alternatively, you can turn off Content & Privacy Restrictions. You should now be able to activate 1Blocker extensions in Settings > Safari > Extensions.
If these Screen Time restrictions are crucial for you, it's okay to enable them once 1Blocker's extensions are activated. This won't affect the current state of the extensions because the restrictions only prevent the user from changing extension settings.