So we should throw away all the 7200s and similar routers today because they are in the way of growing numbers of long prefixes, replacing them with new routers manufactured since the time of the above-mentioned lesson?
No. Not at all. But nor should we cry wolf and defend our corporate policies with phoney hysteria. If you are filtering to keep your internal routing tables clean fine, to get the most out of your older or less than optimum equipment, fine too, but don't say the "the internet is in danger of imminent collapse if we don't do this" either.
And when shall we throw away the 12000s and similar routers (or components thereof) because they are underpowered in the face of routing-table growth, compared to well-established alternatives?
As soon as it becomes pratical. But again, don't defend the (legitimate) position of wanting to get the most mileage out of your installed equipment base or *not* wanting to spend millions of dollars on forklift expansion by saying that its for the good of the internet. Although this is certainly the first time I've seen ivory tower idealism (aka nice clean routing tables with short allocations) match up to the goals of a real world corporation (aka lets encourage customers to buy our service and at the same time prolong the life of our core routers by a year or so).
Incidentally, the lesson learned was that sheer storage AMOUNT is only a (perhaps small) part of the problem, compared to the processing necessary to use that storage in support of dynamic routing (in terms of CPU and in terms of accesses to that memory).
Historically router CPU technology has lagged behind the server industry, at least in raw processing capability. Well, there was the fine machine made by Bay, but that proved beyond a shadow of a doubt that faster with more memory does not a stable router make. But that's a different thread. -vb