Totally false. It is a technology problem. Apple is at the forefront of engineering technical ways to make it impossible for them to decipher your data.
Specifically HealthKit data "is stored in Data Protection class Complete Protection, which means it is accessible only after a user enters their passcode or uses Touch ID or Face ID to unlock the device." Furthermore, "When configured for iCloud storage, Health data is synced between devices and secured by encryption that protects the data both in transit and at rest. Health data is only included in encrypted iTunes Backups. It is not included in either unencrypted iTunes backups or iCloud Backup."[1]
You also provide zero evidence that "Apple will sell your data" even if they could get it. Nothing in that citation about using China-based servers supports it.
Specifically HealthKit data "is stored in Data Protection class Complete Protection, which means it is accessible only after a user enters their passcode or uses Touch ID or Face ID to unlock the device." Furthermore, "When configured for iCloud storage, Health data is synced between devices and secured by encryption that protects the data both in transit and at rest. Health data is only included in encrypted iTunes Backups. It is not included in either unencrypted iTunes backups or iCloud Backup."[1]
You also provide zero evidence that "Apple will sell your data" even if they could get it. Nothing in that citation about using China-based servers supports it.
[1] https://www.apple.com/business/docs/iOS_Security_Guide.pdf