Once basic needs are satisfied you cannot double-satisfy them. Paying for twice the amount of food does not make you live twice as long. So that's a fixed demand, while luxury goods are unbounded in their potential costs.
If you subtracted all that value spent on basic needs there there still would be a lot of capital flowing around.
I think the ancestor comment is arguing that there basically are two separate value circulations. One to distribute and allocate the essentials and the rest for social-value-signalling. Maybe that's also something UBI gets wrong. That we actually would need two currencies.
Post-scarcity scifi settings often feature something like that
a) all the basic stuff including housing is essentially given away for free
b) you get a fixed amount of luxury resource allocations on top of that
c) you can gain additional ones via some kind of work
d) they can be traded if others find whatever you're doing valuable.
so you don't have to work for the government or megacorp.