This is a common argument used by those who want to oppress others; here's the flaw in it:
I agree! It is none of my business and that's the whole point of liberty: Individuals should have self-determination; that is, freedom. Their choices and interests are none of my business, and they are none of their oppressors' business either.
If they don't have the self-determination to control their own lives and express their own interests, then often there isn't much they can do to get it; their oppressors hold the power. That's when other people have a responsibility not to close their eyes to oppression but to do something about it. The goal is not to tell the oppressed what to do, but to give them the freedom to decide and act for themselves.
I know I have my self-determination and freedom because of the efforts and sacrifices generations of others have made for me; millions have paid with their lives and their fortunes; more gave up careers, went to jail, suffered ostracism, torture and worse; generations made it their jobs to make laws, creating institutions and more to ensure I have my freedom today. Is my response that it is none of their business? Or do I have a share of the work to do?
That's certainly true of some people, but note all the people throughout history (e.g., in my prior comment) who have made great sacrifices for it. If nobody was willing to sacrifice, there would be no freedom or democracy today.
Because that creates political friction, leading to conflict, leading to profitable arms sales. So much of the US's cavalier foreign policy is geared toward propping up the MIC between the periodic big wars it takes on for itself. Eisenhower's warning came true and nobody is doing anything about it.