I don't think it will illegal.
It will not be illegal if your country isn't aware of bitcoin gambling or they are simply supporting gambling and bitcoin at the same time. But don't be confident because each country will know about bitcoin and on how it can be used. Most of the countries now are aware of cryptocurrencies and they are all making rules and regulations to it but as long as there's no clear directive about bitcoin gambling, it doesn't mean that its illegal nor legal in your country.
I dont agree with your statement because I dont think in this world of technology, there is some country which is unaware of bitcoin gambling. Every country whether it is a Muslim state or non Muslim state, people are well aware of such beneficial things as they really are beneficial but only when we see and focus on their positive side. Officially, bitcoin gambling is considered to be an illegal activity as it is against the morals of humanity but still alive in many countries.