Count me as another who views these demands by the union as counterproductive, while supporting UBI at the same time. I submit that we're under-represented on HN, canceling out the opinion that we're over-represented

I think your guess about the overlap between UBI supporters and supporters of these union demands is way off base, and is serving to distract from the substance of the matter.

The unions should be advocating for fair pay for employed union members, but not for unlimited jobs forever. If anything, the union has money and can provide a salary to laid-off employees.

Alternatively, maybe unions should be advocating for UBI and advocating for their members to do the same, and to vote for the politicians more likely to support UBI.