A Link Rot Bestiary/Chapter 6 : Usurpation
Usurpation is when a domain has been hijacked by a spammer. They re-register an expired domain and redirect traffic to their servers which contain unwanted content. It is a variety of soft 404.
As the Internet ages and more domains go offline, spammers look for dead links on sites like Wikipedia and elsewhere to determine which domains have a large number of links. They then re-register the domain and send viewers spam content. The classic example is Asian gambling sites, who control thousands of domains scoured from Wikipedia. In this way they spam Wikipedia without ever needing to make an edit.
A system has been established on English Wikipedia to report the domains so they can be converted to usurped status.
Nevertheless, the problem exists Internet-wide. For example there is a domain on GitHub with over 700 impressions in repo README files that has been usurped - fixing these would require submitting 700 push requests to each repo and hoping the owners follow through.
As can be seen, the problem is large, intractable and will only increase as more bad actors discover how cheap and easy it is. The long term solution will be cooperation from domain registars. Until then, this special class of soft 404 is notable.