But this one is true. Apple obviously puts out slowdown updates right as they release a new phone. They made my iPhone 7 unusable the same week they released the iPhone X.

Apple announces all iOS updates in June and releases them simultaneously with the newest iPhones in September. So you're right, but only trivially so.

Do you have some actual evidence that this is the case ?

Otherwise saying it is definitively true is misleading to put it mildly.

Replying to you from an iPhone 7 that I use daily.

I'm very happy with my iPhone 13 Mini, my wife is very happy with her iPhone 12. They feel exactly the same as when bought new.

Whatever is it that you're saying that Apple does, it's either not obvious or they're shit at it.

if conspiracy makes hundreds of billions $$$ then nothing stops people really.

like Charlie Munger have said: "Show me the incentives and I will tell you the outcome"

I don’t think your overall take is wrong (it’s about money), but maybe the simplicity of it is.

Reality is that designers, product managers, engineers — they all wanna build cool things, get promoted, make money etc.

You don’t do that by shipping plain designs, no matter how tried and true. The pressure to create something new and interesting is ever present. And look we have these powerful Apple silicon chips that can capably render these neat effects.

So no I don’t think it’s a shadowy conspiracy to come after your iPhone 8. Just the regular pressure of everyday men and women to build new and interesting things that will bring success.