This is hard to answer, but to have a universal basic income the money needs to come from somewhere. The idea with governments starting a ubi would be plausible because they collect taxes from their citizens, which they can use to pay the citizens a livable wage. With the blockchain, where would the money come from? If you were to create something like this with blockchain technology, it would have to be constantly funded and powered by investments into the coin itself, with the price of the coin rising with more buyers but dropping much more because of all the people who received free rewards for existing. In theory, it could be possible, but it would require so much money to come from somewhere, without the program being able to make any money other than selling the coin.