they should offer
a link-maintenance feature
that regularly checks for
and either
automatically substitutes
a link to the waybacked version
or searches for similar pages
and offers the author a best-guess substitute
(or three)
or best
remembers the original searchpattern
(cf google search history)
that led you to the (now rusted) page
and runs that search anew
offering one-click link-substitution
of the best replacement-link available
.