At the time of writing, the definition of the tag is:
Self-defense or private defense is a countermeasure that involves defending oneself, one's property or the well-being of another from harm.
The expended descriptions touches on defence against armed and unarmed assailants, the law, and mental stress. This makes this a huge area.
While some questions have been really good and useful, others have been little more than wishful thinking in hypothetical situations. Yet, all are covered under that tag.
There is a world of difference between sexual assaults, rape, a "friendly" bar brawl, a street mugging with a weapon, and an assassination attempt. Yet all are covered under that tag.
There is a world of difference between "self defence" in a small student town, a city whether run down or affluent, ghettos, favellas, and war zones. Yet all are covered under that tag.
This does not even touch on whether the defender can use unarmed, mêlée, or ranged weapons in their jurisdiction.
Martial arts are only a tiny element of self defence. This site is about martial arts, not self defence. So, should many questions on self defence should kinda be off topic?
The law on self defence is complex, varies from local to local, and we certainly should never, ever, give legal advice nor should requests for legal advice be answered in anyway. This, should be off topic for sure. Some things that are legal in some countries might lead straight to jail in others: for example, carrying a concealed weapon in the UK vs some states in USA.
So, what can be done?
I have no idea thus me asking the question so that the community can reach an agreement.