> They are putting themselves 'above the (social) law'.

There is no “social law”; not in the US, at least.

We have never been more divided as to what constitutes appropriate behavior in public. We are not an ethnostate (nor should we be), so all social behavior in the public at-large is essentially undertaken on a battleground. Every ideology, sub-ethnicity, and social group has its own competing norms that often conflict. At times, expressing behavior that is normal (for you) can inadvertently become a political statement and a call to conflict.

Talking loud on a train, as you mentioned, may be unacceptable to some and perfectly normal to others based on culture. Not to mention biological aspects such as neurodivergence.

“Regulation” also does not happen in a vacuum. Regulation imposes a particular viewpoint, one that all may not agree with. These days, the majority may even disagree with the imposed viewpoint, as our ruling class is compromised.

“Implicit regulation” through vague norms is even worse, as you are inevitably oppressing some groups based on their cultural characteristics, and not letting them argue against it. Laws can be debated at least, even if they are bad laws.

It may be that multicultural societies are doomed to implode. (I certainly hope not.) If we are to have a chance of keeping them afloat, light-touch governance and permissive norms are probably the only hope. Perhaps this can be coupled with voluntary collective norms that are crafted as a nation. But we can’t object too loudly if some groups don’t hold to these norms, as long as they are not violating fundamental rights (which we must also find a way to agree upon!).