Yes, it changed. Don’t believe everything you see in old threads, because that happens sometimes.
I suppose that’s the counter-argument to the argument here that they be closed after long inactivity… Some forums seem to go that way, some leave them open, and there are pros and cons to each way.
I’m not aware of any problem referencing closed thread in an open one. If you mean referencing from ancient topic to bring it up to date, thank you for updating, as it may save someone from being misled.
There’s no specific goal to keep 60,000 posts in 6,000 topics updated though. It’s way too much work.