Humans are insecure, not the world. Humans are insecure, because humans are hurt. (By other humans, who are trying to secure themselves because they were hurt once, and so on the cycle goes.)
What you label as unethical, insecure or malicious, may be normal life for a person living in, say, Middle East or Subsaharan Africa.
Not everyone is born into a context where they can thrive by themselves without hurting anyone else.
And we shouldn't assume that everyone has a legit path laid out for them so they can be succesful without being malicious.
In corrupt countries, either you become corrupt or you resign any possibility to achieve anything.
In a free market that expresses itself as abusing the law, meaning regulations are necessary.
Subtract our issues that cause us to abuse our fellow humans and our environment, and capitalism is the way to peacefully coexist while keeping making progress.
> If you grow up in a world where everyone is respected and everyone feels secure, your parents didn't hurt you, you were not bullied at school, etc., then the only reason for you to strive to secure yourself at the expense of others is if you have grounds to believe others have such issues and will take advantage of you.
The world is insecure by itself. Security is ensured through working institutions and organizations. And that, sadly, happens way more rarely than people in developed nations think.
In most countries in the world, the institutions are not strong, and the rule of law is relative. Specially to the rich and powerful.
In a society where institutions can't give you security, where there are no ladders to become respected in a legit and ethical way, then malice will be rampant. Because, in that context, that's the only way.