I'll state my preference in case it's helpful to someone who is trying to decide if they should revive an older thread or post a new one on a similar topic.
For me, it's really useful to see a larger array of responses all in one place.
I'll offer an example. Let's say as a DM I want to know people's thoughts on whether a feat is overpowered, and suggested changes to it to make it more balanced.
And let's say over the past year we've seen 10 different arguments for why the feat is not overpowered, 10 different arguments for why the feat is overpower, and 10 different variations on the feat to alter it for different preferences.
If all of that were in one thread, then one of the 10 of a particular category might speak best to my gaming preferences. However, if it's split into two different threads, there is a decent chance (a 50% chance in this rather simplistic example) I will miss out on that.
So, from a utility perspective, it's far better for my needs if it's all to be found in one place.
And I do think that is one of the most powerful things about a message board as opposed to places like Reddit or social media. The ability to refer back and collect opinions on the same topic over a longer period of time is highly powerful for a game discussion where people are coming to look up thoughts about a rule over a period of years. And I think a lot of that powerful utility is lost if that topic is always spread over a half dozen different threads which are much harder to gather and analyze in one place.
So, if you're trying to decide if you should revive an old thread or create a new one on an older topic, for me at least I would encourage you to revive the old one. Future readers may thank you.