If you were to look at Baelish's actions -- like arriving with the Knights of the Vale to help Jon Snow win the otherwise surely lost the Battle of the Bastards -- it's also possible to view him as a pragmatist. Like Varys, he's put his considerable mental energy behind supporting a brave, noble leader. He's providing counsel and mentorship to Snow's half-sister Sansa Stark. He's even brought some military might to the table. What a good guy, right?
Not exactly. Baelish's loyalty to the Starks is borne out of his creepy obsession with Catelyn Stark, which he has now channelled into an even creepier obsession with her daughter, Sansa. He doesn't have a secret bleeding heart like Varys; instead, he only has more layers of personal ambition. That's always been bubbling beneath the surface in any Littlefinger scene -- Gillen remains a master of furrowing his brow in a squirm-inducing way -- but last night he brought his lusty intentions to the surface by basically telling Jon, in a leaky crypt no less, he wanted to have sex with his sister. Not a smart move. Snow reacted the way you'd expect: grabbing Littlefinger by the throat and seething, "Touch my sister and I'll kill you myself."
Littlefinger might see himself marrying Sansa like he married Lysa Tully, his moondoor-bound ex-wife, and gaining control of the North. In his roving eyes, powerful women are objects to be coveted, tricked, and eventually discarded. He has no interest in taking orders from a female leader or even managing the nuances of a genuine partnership. Unfortunately for him, the gender-dynamics of the show appear to have shifted beneath his feet: Cersei Lannister is now ruling King's Landing, Arya Stark is killing her way across the map, and Sansa, his would-be romantic partner, has just gained control of the North. And Sansa is not like Lysa: She's more of a threat to Littlefinger than Jon Snow -- just ask the dogs who gobbled up Ramsay Bolton last season.
There are plenty of reasons to think that Littlefinger's days are numbered, but it's important to keep three things in mind: (1) Jon's threat means very little because he's about to leave Winterfell anyway to go meet up with Daenerys (2) As many internet sleuths have pointed out, the framing of the choking moment was almost exactly the same as a shot from Season 1 when Snow's father Ned Stark attacked Baelish and soon met a lethal fate (3) Littlefinger doesn't die.
With the series wrapping up soon, that last point is debatable. (Despite the cool visual echo, I'm less worried about Jon Snow dying -- we've been there and done that already.) Could Sansa -- or perhaps Arya -- fall into his trap? It's hard to imagine Benioff and Weiss not wanting to keep Littlefinger around for the moment when the music stops and the game of musical thrones comes to a close. Like Varys and Tyrion, he's too essential to show's cynical vision of how power operates. More than anything, that's what keeps him alive.