Agreed - however my concern over this suggestion is the potential impact that locking down our content behind a registration-wall would have on our SEO ranking. Our community won't continue to grow if we're not easy to find.
For additional context, our community began life behind a registration-wall on a different platform and the founding members agreed that taking the forum out into the open was the right thing to do for the long-term future of the community. Hiding our content again would feel like a backwards step, and whilst we want to support the member in question, we can't put their needs over the needs of the community at large... which is why this feature request came to mind - seems like a good solution to help protect our members in specific cases like this without negatively impacting the visibility of the community.