Richard Knoppow wrote:

It would be interesting to know what the new film caps
will be like in fifty years but I probably won't be around
then (but you never know what developments there will be in
medicine).

I suspect they'll be hanging in there. Some, actually many, of the film
caps from the 1950s are still reliable and I can only guess that modern
ones will be better still...with the exceptions of some that may turn
out to have come from crummy manufacturers.