Just because something will never be made again, does not make it more desirable/collectible
When we discuss leaded chips (like when someone asks, "What is the allure of leaded chips??"), I think it's fair to say we're speaking in
generalities.
As shared, leaded chips
generally have more history, more nostalgia, wear better, arguably feel & sound better, and have a higher
likelihood of shaped/textured inlays which are desired by many. They're not collected
because they are no longer being made; rather the fact that they're no longer being made
influences how (and yes, sometimes even why) we collect them.
So when rating or contemplating a particular leaded chip or chipset, it is done so with the appreciation that a better one
will never be made. This also makes it much more difficult to acquire leaded chips in the ideal color, condition, complete sets, whatever else a given collector seeks. It can be a serious challenge, which is easily and often summed up with the phrase, "They're not making any more of them." Because it's true.
In contrast, when the next closed casino chip is released, you can bet your bottom dollar that a cooler, cheaper, better condition, sharper label chip will come out next month. Why? Because they keep making unleaded chips! That is not a luxury for leaded collectors because leaded chips are
no longer being made.
I think it's safe to say that when comparing two
equally defined, potentially equally desirable items, the one no longer being made will
generally be more valuable than the one still being made.