As for plausible deniability, I suspect that it's not always a question of wanting to maintain it vis-a-vis your conversation partner, but vis-a-vis a real or imagined third party/society/Big Other:

e.g. I may want to signal clearly to the customs officer that I'm willing to bribe him, but maintain plausible deniability in case his superiors are listening in, so as not to get in trouble, or I may want to signal clearly to the girl at the bar that I'm flirting, but if rejected I want to be able to tell my friends that I was just complementing her shirt and not really interested (or be able to retrospectively construct such a story in my own mind), so as to preserve ego, etc.

The overcoming bias link in footnote 3 is broken, here's a working version:

https://www.overcomingbias.com/2007/06/against_free_th.html

I think both claims are true but on different time scales: (1) yes, the information and discourse readily available to the median internet user is less free and diverse today than it was a decade or two ago, but also, (2) this information and discourse is still more free and diverse than what the vast majority of people would encounter anywhere in the media pre-internet.

There are discussions to be had about which of these trends are more important, for "society in general", or in more specific context, or how things will play out in the future, but I find it very hard to believe that these facts are not both true.

Not saying I endorse these fully, certainly not to the extent of them being the "whole plot" and making other considerations irrelevant, but I think they both contain enough of a kernel of truth to be worth mentioning:

1) While not quite an existential threat, climate change seems posed to cause death and suffering on a considerable, perhaps unprecedented, scale within this century, and will likely also act as a "badness multiplier", making pre-existing issues like disease, political instability and international conflicts worse. Absent technological advances to offset these problems, the destruction of arable land and increasing scarcity of drinking water will likely increase zero-sum competition and make mutually beneficial cooperation more difficult.

2) More speculatively: due to the interconnectedness of the modern world, our increased technological capabilities, and the sheer speed of technological, cultural and political change, the world is becoming more complex in a way that makes it increasingly hard to accurately understand and act rationally in - the "causal graphs" in which people are embedded are becoming both larger and denser (both upstream and downstream of any one actor), and unpredictable, non-linear interaction between distant nodes more often have an outsized effect - black swans are becoming both larger and more common. The central plot is that everybody has lost the plot, and we might not be cognitively equipped to recover it.

Thanks! I appreciate the feedback, and I'm glad to hear my thoughts were in the right direction and helpful to others.

As far as I understand, at level 3 ostensibly factual statements are instrumentalized in the service of ideological concerns (ideology is the deciding agent), whereas at level 4 ideology itself becomes a malleable object that is instrumentalized in the service of the pursuit of power (in the limit case, Moloch is the deciding agent). At level 3, what matters is that your side is winning, at level 4, what matters is that you're on the winning side.

Level 1: "There's a lion across the river." = There's a lion across the river.
Level 2: "There's a lion across the river." = I don't want to go (or have other people go) across the river.
Level 3: "There's a lion across the river." = I'm with the popular kids who are too cool to go across the river.
Level 4: "There's a lion across the river." = A firm stance against trans-river expansionism focus grouped well with undecided voters in my constituency.

I too have trouble thinking of a non-political real-life example (professional politics, at least by reputation, very much seems to be a level 4 discipline), so feel free to disregard what follows, but a striking example would be some hypothetical ex-Soviet functionary whose career trajectory dictated seamlessly shifting between being a communist in the 80's, a liberal democrat in the 90's and early 2000's, and a conservative nationalist by the 2010's.