YES you should not bring any technological devices with you. In fact it is better to abstain from digital systems for a period of 3 months before entering and after leaving China. (Viruses, etc)
DO NOT think your anus is safe. I had a friend who tried to smuggle in 3tb of Xi Jinping x Winnie the Pooh fanfics by encrypting it with AES-1024 and storing it on micro SD cards in his rectum. Little did he know, that day they had started doing mandatory anus probes on all foreigners. They found it. They cracked the encryption in a few minutes due to Chinese quantum supremacy and needless to say, he was executed on spot.
DO NOT think about the CPC. They have theta-brainwave detectors at the border and can detect revisionist and counter-revolutionary thoughts. Especially if you have any information that could lead to the downfall of the CPC.
Seriously though, what are you expecting to happen? What privacy are you expecting to lose? What laws for discrimination are you expecting to be missing?
When you travel internationally you already lose some privacy in that they have your passport. You are telling them exactly who you are, and where you came from. Some countries will take fingerprint scans (US, China too). Those are pretty big but are not specific to China. You should disable biometrics on your phone though, as that means they cannot force you to unlock it. But regarding the tech on your phone, if you are using any google or meta services, then all your privacy is already gone and Chinese authorities can just buy that information if they want. So I’m not sure exactly what you’re worried about, some specifics might be useful.
It would also help to know what you want the cloud storage for. They can’t suddenly hack into all of your accounts the moment you cross the border. If you already have sensible security steps like strong passwords and MFA in place, then I don’t see what else you’d need to do.