Establishing UBIs? Yeah that's been hard.
The UBIs themselves?
It hasn't been tried on a large enough scale yet, but the evidence from the trials that have been done is very encouraging:
https://basicincome.stanford.edu/uploads/Umbrella%20Review%20BI_final.pdf
@dingodog19 @hunkyscotsman @whalecoiner that's not a real person you're replying to. He's sucking off Elon in numerous posts.