[anyfoo]

I didn't say it's sufficient, but without the preservation that the Internet Archive does, we'd be completely lost.

I have come across some wealth of deeply technical information by entering dead links on still live pages in the wayback machine, and then following crosslinks from there to further old sites. I shudder to think what would have been if I hadn't found the dead links in those cases, and I'm sure I still missed a lot because I didn't know it was there. So yes, this is a very real problem.