The subject is how does bitcoin affect the world's economy?
The same as the normal country's economy from different sectors of source of income. When someone earns from bitcoin, he will contribute to his/her countries economy by having the purchasing power.
does it do well to it because it stops inflation as the amount of it is limited?
It does well because there's a big market cap of it.
or does it harm it ?
It harms only depending on its usage just like cash.