I am 100% in favour of archiving and I agree with your point entirely. My frustration is directed towards those who believe that within the next few decades, printed books will be obsolete.
I tend to agree that we have a little time, but then again these things happen quickly when they happen. If you don't prepare in advance, you end up trying to invent your archiving plan in the middle of the fire sale.
This needn't actually be that hard if we do it systematically.