You can't really claim something is end to end encrypted if you don't have access to the client source code to verify that this is the case. There is no good reason to trust any company for sticking to their words, especially under pressure from the government.
Because that’s what Apple says and Apple generally doesn’t lie about their products. If you don’t believe them then the onus is on you to prove it, not for someone else to disprove it.
We do have clear evidence that Apple devices track our location, and we do not have ability to turn it off. We do not have evidence that logs are not kept or shared nor of the E2EE of those recordings. This is not conspiracy theory. We are asked to be credulous of how the largest market cap corporation in the world handles this valuable and sensitive data. The onus is on them to prove what they say, and if they cannot, I do not buy it.