Now we are in 2019, did Bitcoin make a step to be a leading cuurency?
What do you mean by that? Bitcoin is the leading crpyto currency in the market and I don't think there would be another crpyto that will surpass bitcoin. It will not make a step since it is already ahead of other altcoins in the market. It is now 2019 and it is still the leading currency despite that fact that it is been a long time since its release. It just proves how strong and patient its users and investors.