From the article:

There is consensus to immediately deprecate archive.today, and, as soon as practicable, add it to the spam blacklist (or create an edit filter that blocks adding new links) and remove all links to it. There is a strong consensus that Wikipedia should not direct its readers towards a website that hijacks users' computers to run a DDoS attack (see [WP:ELNO#3]). Additionally, evidence has been presented that archive.today's operators have altered the content of archived pages, rendering it unreliable.

Evidence was presented here: https://en.wikipedia.org/wiki/Wikipedia:Requests_for_comment/Archive.is_RFC_5#Evidence_of_altering_snapshots