I think I'm getting what you're trying to ask. So, you have…
- a feature request about non-anonymous downvoting
- this feature request closed as a duplicate of one of the
thousands dozens of other feature requests asking for a mandatory explanation of downvotes
And now you're asking if you should post your new proposal as an answer to the older question, or keep editing your new feature request so that it doesn't constitute a duplicate?
Either is fine.
You're free to post a (complete) answer on the other question, suggesting an alternative UI or workflow. People here do that all the time, and it wouldn't be the first time Stack Exchange implemented what an answer suggested—not the original question.
It's also okay to make your new request distinct from the previous one and have it reopened. Just explain why it's different. As icing on the cake you may list all the other requests you've already found.
Please don't do both, though. If you have a similar request, post a comment on the older question, linking to it. Don't hijack the older question by posting an answer with a link to the new one.
But remember that for topics such as "require a downvote explanation", the Meta community is at the point where it doesn't even want to see any new request in that direction. The incentive to find a somewhat related duplicate request and close the new request is quite high—nobody wants to be dragged down the same old discussion every time somebody complains about getting downvoted anonymously. The majority does not want to be forced to explain their rationale for voting every time they click the vote button.
To sum it up, I see you're trying to participate actively here, suggesting new features, trying to find out how Meta works, but I suggest you take it a bit slower, read through the discussions we've already had, see how the community reacts to new suggestions, et cetera. Believe me, there are several requests about downvote explanations per week. Maybe even per day. Don't get your hopes up high to change this (core) aspect of the Stack Exchange sites.