I don't think any libertarian minded individuals actually believe in tossing out all safety nets and most likely don't care to reduce taxes on the wealthy either, at least not as a goal in and of itself.
Even so, he's basically on your side in the sense that whatever UBI ends up being proposed for law, he would probably vote for it.
Personally, I think we can definitely eliminate the some of the costs of the social programs by giving everyone a flat $30-$40k per year.
The driving difference in thinking being that I believe that the only viable way to make basic income happen is to assess average living expenses across the board and provide that amount to everyone while retaining the former programs at a much smaller scale.
One of the big issues with the current system is that there is a lot of trouble in determining whether a person really needs the assistance of a program or not. UBI helps in that only those who can show a need beyond $30-$40k/yr need apply.
It's not a bad thing to say, "we have gotten so good at being productive that we've made work essentially optional".