When you immigrate into a country, all of a sudden all of your reflexes are wrong. Some are obviously wrong. Some are more subtle. It is overwhelming, and too much.
While in retrospect it is easy to say that they should prioritize some things over others, in practice they tend to learn from experience after people respond badly, and those who are a little more used to the culture explain why they are wrong. And the experience of being told that they are wrong all of the time will make many hold on to some of their old habits extremely strongly.
Don't criticize how slowly immigrants adapt to a new country, until you've been an immigrant in a foreign culture.
I agree with you that it takes a while to adapt to new sociale mores and it's worth cutting immigrants some slack but that's different from driving a multi-ton heap of metal where safety is important.
Sidenote: Of the different cities I've lived in Asia, HK drivers are some of the worst. Combination of aggressive driving with refusal to signal their attention (by using their turn signal) makes for very poor driving. Not everyone but a significant percentage.
I am an immigrant and find this line of thinking to be a cheap rhetorical trick, a thought-terminating cliché. Yes, people who are not immigrants can share their opinion on the behaviors of immigrants. Maybe we can all learn a little from each other instead of gatekeeping anybody who has had a different lived experience.
Can I ask if you've ever lost someone you love because of a mistake made by a driver?
I'm sorry to have to say this so bluntly to you but migration status is not an excuse.
You should get lessons if you're unsure how to drive correctly and if you can't follow the local rules of the road you shouldn't be driving at all.
The problem here is not what you know that you don't know. It is what you don't know that you don't know. You can believe yourself safe, when you aren't.