You can find reasons here
https://www.bloomberg.com/news/articles/2018-04-23/how-malta-became-a-hub-of-the-cryptocurrency-world-quicktake
Interesting article. Thank you for sharing. I did not know this :"“The proposed framework will offer legal certainty in a space that is currently unregulated,” the government said in a consultation paper. A national tax policy that permits international companies on the island to pay a rate of as little as 5 percent doesn’t hurt, either."
What does this rate of 5% apply to?
It may be related to the percentage they take after changing crypto to fiat
I would say all businesses have to pay some tax, so maybe this is their toll on the general tax?