Yes. Both countries have highly invasive laws and will demand access to many things.
DO Bring a completely clean and clear Burner Phone. Do not log into anything on it, do not download any apps, or sideload necessary apps when you can, do not do anything besides basic activation.
DO invest in personal private cloud storage but make sure it’s hosted somewhere SAFE and that you won’t have issues getting through the Great Firewall (China) to it. Make sure you paid up to host it for the duration of your stay BEFORE you leave your home country.
You are not freaking out! It’s perfectly fine to protect your privacy and it is NOT illegal. You cannot predict when or if you will have a run-in with local authorities in some countries. It’s best if those authorities have nothing to hold you on.
Having a clean, secure, and private device which does not leak any unnecessary information about you when seized is ideal.