I do think it's as much of a fallacy to say that "we're in decline because X happens more/less" as to say "we aren't in any sort of decline because Y happened before" simply because society isn't homogeneous and even if morality could be described as a function over time, it certainly isn't monotonic. Besides, most of the time the arguments are made using whatever handpicked examples are at hand, instead of any empirical measure... and even if you want an empirical measure, I doubt they are always as available as you'd like (am I right Battuta?) or even in the same frame of reference.
EDIT: Iss just said a lot of what I meant: we have a skewed view of the past anyway, and there's not much we can do about that.
As far as technology goes, it is simply an enabler. It certainly can be used for good or evil, to make society better or worse. But it's no more responsible for any of that than a hammer is for building a house.
(But if you are on the verge of introducing technology Z, know that it will probably be used mostly for bad purposes, and choose to introduce it anyway and enable people to destroy themselves, are you morally responsible? Good philosophical question, but tangential).
That said, I do worry that modern western society is heading in troubling directions... mostly that as we get more connected and involved in the virtual world, we become less connected and involved in the real world. We're abstracting ourselves away from reality, and I worry that the consequences of this will be more bad than good.