That's not always true, a UBI doesn't say anything about its funding mechanism. Some UBI proposals are indeed funded on tax revenues and thus revenue neutral.

Corrected.

Central banks only print paper, the money is created by creators of value, and about half of that volume of value is being taken away from them by taxes.

I think GPs argument is that the demand for dollars is so high that you can print them with few repercussions (inflation).

Precisely.

Inflation steals future opportunuties from those who save money, and it generally steals future from new generations to come. When a family opens a bank account for their newborn child to use it for paying for their higher education, they do it in a hope that this money will preserve its value.

This is how the modern economy appears to work. There is no guarantee of return on capital, or that capital must hold its value.

https://www.visualcapitalist.com/700-year-decline-of-interes...

https://www.stlouisfed.org/publications/regional-economist/f...

But this just states the current situation, when paper is being printed without any relation to material implementation of the value that it's supposed to represent. The fact doesn't justify the policy. Economy depends on producers of value, not on a printing press. I can exchange values without a means of paper.