This. There is compelling evidence that UBI, over the short term, really is effective at distributing money to a lot of people in need without a cumbersome burden of proof placed on assessing that need. That's why the treasury department used it for stimulus checks in the US. But long term, we don't understand if UBI is an effective tool for dealing with poverty. In effect, UBI would be like arbitrarily adding $15,000 to every persons annual salary. Over the short term this would be great. You'd be able to cover the costs of your bills with that additional money and live a little more securely. But in time, the market would absorb this expansion of the money supply as inflation. More surplus money in some people's pockets would lead to increased demand for goods and services. Increased demand would lead producers and retailers to charge more for goods. Renters would get charged more for desirable property. Gas stations would charge more for gas. And over time, your UBI check would need to get bigger and bigger to carry the same purchasing power that it did when UBI first started. There are examples of what this runaway inflation looks like in countries that pump free money for extended periods of time into their economies. Venezuela comes to mind.

To be effective, UBI might work better if it's distribution were random. And the duration of payments were irregular. Something that a market couldn't set it's watch by and producers couldn't game. If this sounds a ridiculous long term solution to poverty, it's because it is.