Jon could have received the Lonely mark in s4 even without chasing m*rtin into the domain. tma has never defined the Lonely as purely self-isolation; that’s certainly a dimension of loneliness, esp. when the Lonely can be read as analogous to depression, but it’s by no means the definitive one. its primary avatars are the Lukases: a cold, cultivated loneliness that’s not self-imposed, but created by a group of people abandoning a person/each other.

there’s even a pervasive sense of outside hostility associated with the Lonely. Naomi Herne is rejected by the Lukases; Boatswain’s Call, Personal Space and Peter Lukas’ ritual are all about consciously choosing certain people to cast out; Lost in the Crowd and Monologue have an element of other people becoming unrecognisable and, consequently, the victim losing a sense of belonging. Cul-de-sac had a breakup and loss of mutual friends as its catalyst. even Mordecai Lukas was explicitly shunned by Jonah Magnus in favour of knowledge.

my point is Jon didn’t need to be immersed in the Lonely because he was already deeply alone at that point in s4. the loss of humanity made him feel alien enough to the other people, and Basira certainly wouldn’t shut up about it (i.e., hostile rejection). despite their initial connection in the season, Daisy was later too far gone in suppressing herself to be much of a friend to anyone. Melanie severed her connections as much as possible with the archive staff and sought companionship/understanding outside. Tim, arguably the only real friend Jon had in the entire series, spent his final months blaming Jon. and does being the only one to remember Sasha’s voice just not isolate him further? Jon even admits to Martin that a part of the reason he sought him out was because Jon himself was lonely.

we’ve talked a lot about the massacre of Jon’s autonomy in s5, and while not being in control/inevitability is almost a prerequisite to cosmic horror, the tragedy of it all happens on when characters actively struggle against it. in vain, of course, but there should have been a struggle. by which I mean… imagine if Jon had rejected the choice to go after Martin. Elias would still have given that choice to him bc Elias likes to be absolutely certain of the marks (à la letting Prentiss’ worms squirm around in Jon a bit before engaging the suppression system), but imagine if Jon was already so abandoned, so marked by the Lonely in his own right that he rejects the burden of saving Martin. that there’s nothing in him that wants to save anyone anymore.

what a set-up for the apocalypse that would have been, especially considering how much of s5 focuses on social horror. Jon’s awed, terrified delight at the final two or three sentences of MAG 160 could have been the entire statement because here is an Archivist finally willing to sacrifice the world of his own free will because he can no longer see a reason to salvage it.