I think keeping feature requests open until they’re complete or denied would be better than the current situation, because it would allow us to vote for and discuss large but important long-term projects while they are still in progress.
I want to distribute my votes to my most desired features, which have mostly turned out to be ones which the staff and developers are already planning to implement. There are so many feature requests in progress that I would like to vote to help the developers prioritize.
I’ve seen some valuable new ideas which were only posted after weeks of back-and-forth discussion. That kind of community input is most valuable for the big features which take a long time to implement, but right now those are the feature requests which are getting closed right away.