Currently funnel pages are not blocked so they may be viewable by those who have the direct links to them.
If you have pages that have content on them that you do not wish to have available to anyone who finds the page, you can use our custom experiences to show/hide content. You can show/hide content based on a URL parameter as well, which could work similar to the funnel gateway key we had in previous OptimizePress versions.
We will not be adding a funnel gateway key to the new OptimizePress as we found it was not a widely used feature and caused more confusion for those who wanted to setup funnels. Modern funnel builders do not generally have those features as they are considered an outdated way to create funnels.
If you have any questions about this please reach out to our team and we'll be happy to help.