There is much to be said for carving out means of raising the productivity of the marginal. I don’t think Dampier would deny this. I suspect he thinks there are better ways to accomplish it than UBI.

I expect UBI would destroy a country’s industrial base. I will continue to claim neo-Luddites are wrong until one of their predictions come true. All industrial products depend critically on low-skill labour, which will be bid up by the UBI. This will make basic products more expensive, requiring a higher UBI, which will subsequently bid labour even higher, and so on until the country produces nothing or the UBI is abolished.

Equivalently, fewer people making stuff means less total stuff to distribute.
Notably, while American industrial labour has stagnated or even started to chip at decline, America is not really losing jobs to China: the productivity has increased and American industrial capacity was climbing as recently as a couple years ago.

Ironically, a non-universal, particularist basic income is unquestionably better than welfare. Implementing it in towns that have already lost their industrial core solves more problems than it creates.