Bitcoin is legal by some countries but some countries still not accepting the bitcoin.
What you think is Bitcoin become legal in all countries?
That is the ideal scenario, wherein all countries legalize the utilization of bitcoin for enjoying its maximum potential and benefits to the public. But again, there are countries out there who prohibit the use of bitcoins due to its decentralized nature. Meaning, bitcoin is being used as the main currency for illegal stuff, like payments for illegal transaction of drugs or other smuggled goods or things related therein. Every decision that a country accepts has always a negative implication, wherein bitcoin has its own faults. Like everyone said, nothing is perfect.
Personally despite having its faults, the opportunities and benefits it provide to the general public outweighs the negative impact on the country. Due to bitcoin, more people are sustained. Bitcoin can be the equalizer among the rich and the poor as everyone has the privilege of investing into it. Though that again might be the ideal situation, it may be far from now but it will definitely happen in the near future.