But if a police officer were to remove your phone by force, first it would be illegal without a warrant so it would almost made you a favour as all evidence in your phone would be invalid in court.
Even if what they find on your phone isn't valid in court, it can still lead them to other things that are valid. For instance, a picture taken at a specific place with a timestamp. That picture may not be admissible, but if they find CCTV footage of you at that time and place, you're screwed.
Cops can and will overreach their powers, and they'll probably get away with it.
Even locked if they want the info in your phone they are probably getting it. They would have access to some of the best forensics teams and equipment.
Sure, but it's a lot harder for them if your phone is encrypted and shut off before you encounter them.
Following the same logic, should we never have an unlocked phone near a police officer? I don’t know about that.
You really shouldn't. Cops are never on your side.