Why Is This Important?

If you;re going to live somewhere knowing the culture and history allows you to fit in better? Plus simple respect for the people you live with.

I think in general if you care about a place, you care about these things. Especially when you choose to live somewhere, by learning the history and culture it helps you understand why things are the way they are. Why there is corruption, why the streets are like that, why it costs so much, why locals treat you how they do and what can you do about each issue.

this is important for everyone, not just foreigners...

Technically yes. I live in the US. Have a lot of native neighbors and friends

Context matters. History influences how people operate. Looking back hundreds of years is a little iffy but knowing how the cake is baked in recent times can be helpful.

If I moved to another country that spoke a different language, out of respect I would learn the language and customs.

It's not knowing history that's forced on them -. It's the official alternative history that justifies the nation's atrocities that must be swallowed whole.

At a minimum, it helps them adjust faster/better to life in the country they now live in.

It's a touchy subject but basically some countries are not so civilised, so if they want to live in a civilised country, or if a civilised person wants to live in an uncivilised country, then they need to learn some key cultural aspects to survive.

Why is this a question you have to ask?