Just to make this very clear: planned obsolescence (of e.g. iPads, smartphones, but also dish washers or cars or whatever ...) isn't in any way something we have influence over and I'm not defending it at all. On the contrary, I (personally) think that it would be great if software and hardware vendors would actually support devices(products) for a longer time period, even if it's only for security updates (the environmental aspect alone would justify that, I think). I do recognize (of course) that this longer support period would have to be reflected in the prizes of the devices / software / products, as maintenance (obviously) is time and money consuming.
Now, we're in a difficult position in the middle here: If those devices (or the software that runs on it) used by our users no longer get security updates, we would have to risk being infected by some sort of malware every time we use it. This is a risk we could be willing to take, but we're not. If something "big" is hitting us (due to that missing security update), that would mean that LEO might be down for everyone who knows for how long (instead of affecting "only" those users that have such a no-longer-supported device). We like to minimize those risks as much as possible. And we don't actively work towards not supporting older devices or software, but in the process of changing stuff, we also cannot test for regressions anymore.
Even if we were willing to test on old software versions, we would still need to also have some way of testing with the (most) current software version - which would lead to an incredible amount of devices / software configurations we'd need to have on premise. Just to give an example, for the first iPad we'd need to have one with "iPhone OS 3.2", one with "iPhone OS 3.2.1", one with "iPhone OS 3.2.2", all the way up to one iPad with "iOS 5.1.1" - and this is only for the first iPad and only for Apple (things get so much worse with Android smartphones and tablets in this very particular regard due to the many manufacturers...) and only for the stock Safari browser (imagine "But I'm using Firefox 15 on iOS 5.0.1" (made up example, not sure that's even possible). This get's out of control incredibly fast... Yes, there's services for that as well, but this will become a money-issue quite fast (aside from the huge organizational measures needed)
So even though I agree that planned obsolescence is quite a nuisance (to put it mildly, and it's more disturbing in some cases and less in others), and I fully support people personally for using those devices for as long as they're working, our hands (as LEO) are quite tied here and we (subsequently to the original manufacturer / vendor) can't support older versions indefinitely, and we're sorry about that!