For those of us whom cut open filters, I expect we're all generally very careful and diligent when doing so. It's unlikely we'd induce a failure mode by simply cutting open the container and relieving the pressure which exists via the spring to bias the media assembly to the base. We're going to be very gingerly with the filter and examine it first, and only after that, perhaps check things like pleat pliability (which may or may not induce a tear). In this case, I SERIOUSLY doubt just cutting open the filter caused the cap to come off the media.
I can see this both ways. The material is there to first and foremost allow for assembly to happen; the cap is "glued" to the media so it will stay together for unit assembly. But it also serves a purpose to eliminate a potential leak pathway during operation; it's supposed to seal the cap to the media so oil does not bypass the media. Some would argue that if the cap were tight to the glue because of the coil/leaf spring, it should not matter of the adhesion were lost because at this point, the spring pressure is giving the bias for dP to hold the assembly snug.
We should take a step back and ask about design intent. What is present is likely not intended. Do we believe the product design team said "let's design a filter that will loose cap adhesion; we want it to stay together for assembly but then loosen it's grip during use." Is that what we'd believe? Nope - this is a product failure; that adhesion is supposed to be present at all times. Now, again, it may not matter in the "as used" state; the spring pressure may make the adhesion inconsequential once it's fully assembled and fit for use.
It could well be viewed as an assembly aid that is of no value in typical product use. I worked in the automotive industry (Ford manufacturing) for 16 years. I now work in the HVAC manufacturing industry. There are often elements present in a consumer product that may not have value to the end-user, but must be present at some point in the making of the product due to process or shipping issues.
I will be polite and not call out names here ... but I do want to address what I believe to be as hypocritical positions from some of you ...
Here's a loose end cap, clearly not "normal". But if this were a Fram EG or TG and the fiber end cap were loose, the sky would be falling as some bash the product mercilessly. But not a peep about this loose metal end cap from some members because it's not a Fram. Not unlike folks who decry the use of leaf springs in Frams and other brands, but then are eerily silent when an Amsoil filter is laid open and it reveals a leaf spring.
Ah - brand bigotry ...