Someone decided a post was a duplicate, but cited article didn't answer the poster's question. Poster wanted to block cookies, but cited article would block entire site.
If the intention of the asker are unclear, clarification can be requested through comments. In the mentioned case the OP didn’t come back with more details which would have helped to reopen the question. So for all we know right now the linked question helped the OP.
If somebody else is looking for a solution to block cookies without blocking a site, or to avoid tracking by specific sites, there is always the option to ask a new question.
Actually, it was four people: myself, 2 other users and a moderator.
A question can be closed as a dupe by...
- 5 users (with appropriate privileges) voting
- unilaterally by a mod or a user with a gold privilege for the related tag
This doesn't mean it's binding. The OP can edit their post, highlighting what makes it substantially different from the dupe, which will automatically put it in the voting queue for reopening.
In the case of your linked question, the questions are literally exactly the same. The answer is not a good one in that it doesn't address the OP's concern. A better course of action would have been for the OP (or someone else) to offer a bounty on the original question.