Why would it matter the reason of dropping a file of X size? The point is that not all applications are “decent” and some will undoubtedly use /tmp because “it might be the most logical thing” for any developer that’s not really up to date.
It matters because it's the difference between a real-world situation, and a fabricated scenario that you expect to be problematic but doesn't generally happen.
All filesystems have limits, and /tmp in particular has traditionally been sized much smaller than the root or home filesystems, regardless of what backing store is used. This has been true for as long as unix has existed, because making it large by default was (and is) usually a waste of disk space. Making it a tmpfs doesn't change much.
The point is that not all applications are “decent” and some will undoubtedly use /tmp because “it might be the most logical thing” for any developer that’s not really up to date.
In my experience, the developers of such applications discover their mistake pretty quickly after their apps start seeing wide use, when their users complain about /tmp filling up and causing failures. The devs then fix their code. That's why we don't see it often in practice.
I don’t see how reviewing the tmpfs helps in this scenario if at all…
I mentioned it in case it helps you to understand that the memory is used more efficiently than you might think. Perhaps that could relieve some of your concern about using it on a 16GB system. Perhaps not. Just trying to help.
we are talking about end-users your common joe/dane running your day to day applications, whatever they may be.
We are? I don't see them echoing your concerns. Perhaps that's because this is seldom a problem.