I don't see why a filter should really be any different from any other electronic item. I've often heard it said that electronics have an early life failure - a matter of months, or last for quite a few years.
However I'd have thought that realistically the life of a very inexpensive piece of consumer electronics is fairly unpredictable. And the problem with a filter, compared to (say) a cheap radio, is the difficulty of knowing that it's failed.
If it was suggested to me that a filter had failed, or if I suspected the possibility, I'd replace it to see if it made any difference.
We have more and more laws, and less and less enforcement