I can't for the life of me understand why my pops have such low approval.
Most of the pops of the planet are military faction, which has around 70% approval in the empire.
Thought this might be due to the planet gov being a filthy xeno synth, but changing it to a militaristic leader did nothing, even putting stability lower to about 17%, so I'm at a loss.
There's 15k amenities, so everyone should be happy af.
Any advise would be appreciated!

R5: Happy pops not happy, very hateful indeed, they do not approve.
Help please
Go to the economy tab and look at the happiness of the elite, there should be a list of all boni and maluses. Then look at at the specialists and for their happiness. My guess is that the elite for some reason are unhappy.
Thank you, I did this now (didn't know that was a thing) and can confirm thousands of 0% happiness artisans.
I did take the planet from someone but it's been decades.
I have a happiness modifier of -90% "From Pop Jobs", any idea where this is from?
does the planet have a mutagenic pools building? those can tank happiness pretty hard.
I do, I'm a follower of the Toxic God, but It shows 600 mutagenic spa workers giving -3.7% happiness, not 90%
The tooltip for that job is bugged, essentially it shows the base rate of the penalty but the effects of the job, both positive and negative, scales off the number of City Districts.
Disable those jobs for a month or two and see what happens.
OP, you have a 99% happiness penalty
(0.75 x 22 x 6 = 99)
That means you have a job on the planet that is reducing happiness.
Inspect your jobs.
I have mutagenic spas and 600 workers giving -3.7% happiness per the tooltip, but that's nothing close to the -90% the happiness tooltip shows
It is from spas. I tried to search but can't find it but somewhere on this sub someone broke down how it works. Basically the tooltip is misleading/hard to understand but just know that mutagenic spas tanks happiness and it's working as intended.
Edit: It sounds like the way it works is it's -3.7% per 100 spa attendents PER CITY DISTRICT. You are well beyond -90% happiness, that's just the cap lol
Without high bonuses to "Government Ethic Attractions" and "Ethics shift chance" it is very unlikely for pops to convert. "Ethic shift chance" making the biggest impact I think and few sources of it(Egal only Edict and "Hearts and Mind" edict from Ascension Theory tech).
This is why some people really like Synth/gestalt play. Or pop modding such as adding loyalty circuits in Cybernetics.
Did you just take that planet from another empire?
I had a mutagenic spa with 600 jobs.
Tooltip showed it giving me -3.7% happiness and -1.2% habitability.
Demolished it, the -90% happiness debuff went away, planet got 31% habitability back.
Is this a bug or am I not understanding numbers?
Mutagenic (and hyperlube) scale but the tooltip doesn’t update right. -3.7 is if you had 100 muta jobs and no city districts (as it scales off both). The good news is the pop growth scales as well, so you where getting a lot more out of it to have that much of a debuff. The result of this scaling is only gestalts, particularly machine, have an easy time of dealing with the downsides (it’s just amenities for machines who can use some of the pop it generates to build more amenities). There are ways to mitigate the issue and work around it. The easiest solution to still get some value of of the spas is to scale back jobs until the negative is not affecting you to bad.
Looks like it's the politics of the population on the planet that's causing it.
Check what factions the pops belong to. You can then see the causes of dissatisfaction in the faction screen.
https://www.reddit.com/r/Stellaris/comments/1nuw2c5/can_someone_explain_why_my_population_is_so/
You are having the exact same issue I had a few months ago. Go into the Pop job and reduce it from max employment to about 50% or even 25%, happiness will immediately rebound on the monthly tick
If you are a xenophobe, approval rating of a foreign official will be low. Time will fix it as the Oracle is immortal.
Higher job strata have more influence on overall happiness then lower(usually, some builds are an exception). I believe this is influenced by "political power" modifiers
You need to dig into what faction the pop groups on the planet actually belong to starting with your elites and then specialists.
Are you by any chance playing a democracy/oligarch? One of your factions hate you and it just so happens that they all live on that one planet, try suppressing the faction and doing anything to increase government ethics attraction on that planet, they'll eventually switch over to a faction that likes you and increase the approval rating
By the look it has a lot of unemployment. Look on population, usually making them citizens fixing most problem.
Next step, look on what faction they belong. If happiness of this faction is Zero, so will be there happiness. So, in long run you need to shift there ideology. In short term, resettling some of your pop into it and there pop out can solve problem.
See, the problem is that you are not a Devouring Swarm. If you were, they'd just want food.
You are genociding them.
see i actually solved happiness problems by genocide, once you label them for purge, they stop counting as people
I am talking about "displacement". They are being thrown away from their homes.