Thank you, that's an interesting read.
In my case it appears that because every ethos is present, there is a complete lock as none of them wants to go under the minimum thresholds?
My core ethics are pacifist and egalitarian, with 50% governing attraction from One Vision tradition and 100% governing attraction from Hearts and Minds edict. Also notable Hearts and Minds gives +100% to the ethics shift chance.
So here's what the game shows me as the current/desirable percentages:
View attachment 557774
Note: These percentages have not changed at all in the past 80 years.
According to the numbers stated above:
Egalitarian - It's 14% with a desired of 29% which means it's probably exactly half (14.5%) and no pops will swap away from it, but in theory there should have been new pops swapped to it.
Pacifist - 13% with a desired of 18% which means that pops could swap away from it every now and then.
Xenophobe - 14% with a desired 2% This one is interesting, I had xenophobe for the entirety of the game, playing mostly isolationist for the first half of the game, so at first this made some sense, but in the second half of the game I've gotten a large influx of refugees due to neighbouring wars, and went mostly xenophile in terms of policy. The desired effect seems to reflect this, but there's been no change in the actual percentage of followers. The desired is much much less than half so it should be impossible for pops to get this ethic.
Militarist - 11% with a desired 6% This was a weird one since I played pacifist isolationist in the first half of the game, but after I got attacked by an AI this faction popped up out of the blue and despite being incredibly unhappy in a pacifist empire, it stayed at 11% for the whole game as well. They didn't grow but didn't disappear either.
Authoritarian - 10% with a desired 3% This is under half so again, new ones shouldn't be popping up. This one does seem to be reactive on the long scale at least, it's the only one that I really noticed changing % every now and then.
Xenophile - 13% with a desired 26% This is exactly half so there shouldn't be any pops swapping away from this one and again stagnation is the name of the game here, nothing really changed with them, I even endorsed xenophile for about a year with no changes at all.
Materialist - 11% with a desired 7% This again popped up after I got some robots, only a handful, but they've been here ever since with no real changes.
Spiritualist - 11% with a desired 9% These came up after the half-point when I fought a war and conquered a bit of land from a spiritualist fallen empire. Now, them being a fallen empire, they didn't have a lot of pops, not enough for it to matter in the large scale, and sure enough the numbers while increased initially, seemed to not change at all ever since I acquired them.
So as an experiment, I've endorsed egalitarian ethics and supressed every single other ethic in my empire to get the following attraction rates:
View attachment 557778
I will let the game go for exactly 25 years and we'll see if anything changes. In theory, every ethic other than egalitarian should not gain any new pops anymore and egalitarian should not lose any pops anymore, and every year I should get 4% of my pops (since ethics shift chance is doubled) to swap ethics. We'll see if it works.
PS - I don't have any migration treaties and won't gain any new pops from wars. I've also restricted refugees so no new pops other than those grown here, should affect the experiment.
I have 2948 pops total at the start of the experiment, I will note exactly how many I have at the end as well.