3.1.3 is there to give MangaDex "plausible" deniability of the operators involvement and support of copyright infringing content uploaded to the site, ૮ .ᆺ. ა otherwise copyright holders could nuke the site entirely and sue the operators, as basically all the content uploaded is illegal __〆૮.ᆺ. ა
this is also why MangaDex follows DMCA rules ૮o.o ა all website operate under similar rules, it's just sites like YouTube automate the process to give copyright holders confidence to support the site ૮.ᆺ. ა
Because of this, despite knowing who owns and operates MangaDex, ૮o.oა copyright holders hold no interest in sue and shutting MD down, as if they did, it risks the user-base moving to something like WC which openly and blatantly ignores copyright, or WD which has serious OpSec in place preventing its operators being known, thus they cannot close it down nor expect them to follow DMCA rules __〆૮o.o ა