It's amusing that wealthy people agree with UBI, I guess it's a way for them to feel good about themselves without actually doing anything much like the people who collect UBI don't have to do anything to get it.
I agree with UBI, it but needs to be set so low its not an attractive option for anyone with an ounce of motivation or capability to live off of. It needs to be permenantly revoked in certain circumstances such as abuse or tax avoidance, if you leave the country for a significant amount of time you should be disqualified too. It could be administered through a blockchain and made impossible to spend outside of a specific marketplace, it also shouldn't be for long-term savings.
UBI could save a lot of money, taxes would become easier, there would be less programs to administer such as employment insurance, forced retirement schemes, countless tax credits, disability payments, welfare etc. There would be savings with reduced crime and massive savings with reduced administration costs. I don't think it would cost any more than all these Old Age security programs, Medicare and other benefits for the poor and unfortunate. But they would all have to be replaced with UBI and thousands of government employees would need to be let go.
Many people don't like their jobs and plenty of people are very unproductive at their work. Maybe they would be able to do something more productive or that would at least make them happier. A UBI program would have very little benefit to me personally, but I get the concept.