Whether justified or not, a recent news event has brought the concept of "good samaritans" or bystander interventions into question. GeoExpat thread: https://geoexpat.com/forum/342/thread368613.html
Regarding the legal protections offered to actual cases of 'good samaritans', a bit of research shows:
1. Hong Kong does not have any laws specifically protecting bystanders who intervene with good intentions. Rather a person would have to rely on the normal defenses to battery, damage, etc that they would have in criminal/civil cases.
2. Shenzhen was the first city to enact such laws in 2013.
3. In 2017, national legislation went into effect in the mainland.
4. In 2018-19, lots of talk in HK but no action was taken to enact laws. The Red Cross continues to push for legal protections, with a recent press release.
https://www.redcross.org.hk/en/press.../20241016.html
Beyond legal protections, there are legal duties to intervene around the world.
(Blue: legal duty to intervene; Green: legal protections for intervening) From Wikipedia: