I think UBI only works as a replacement and simplification of existing programs. As a way to replace progressive tax with a flat tax and eliminating other food and welfare programs, but essentially ending up in the same place without all the corruption and loopholes.

If UBI is pasted in without cleaning out the existing cruft then it'll just be another mess on the pile.

However if done correctly, and not as a form of welfare, then it will be a vast improvement (in terms of fairness) with no effect on inflation.