The pandemic will deflate most economies. So much so that that attempts to correct for this by injecting cash, controlled intentional inflation, only lightly softens the blow. The US economy is expected to see a contraction of 35% to the GDP this year, which is huge. I believe the great depression only contracted the US economy by around 22%. This great deflation is even after several rounds of economic stimulus, which are largely comprised of giving people money from the government in similar spirit to a UBI.

In this case the goal of stimulus is inflation and it isn't enough to repair the economic disruption.

Despite the sharp and historic deflation this is not unusual though. Pandemics are historically known for economic deflation. Europe experienced a devastating pandemic about once a century for more than 10 centuries in a row yielding plenty of economic evidence to this.

The most important thing to learn from this is that a sudden economic deflation hurts poor people and corrections insufficiently help poor people. Wealthy people are not directly impacted, at all. Attempting to correct for that difference with an economic stimulus, such as giving poor people cash, does not at all balance that disparity.

If anything this current pandemic illustrates that a UBI is an insufficient control for balance. Instead of focusing on what to do about poor people if the goal is to balance the disparities of wealthy people against poor people then wonder what to do about wealthy people. Tax the shit out of wealthy people and use that increased government revenue to grow the economy directly in ways only business can: increased infrastructure (there is more to that than just roads and telephone poles).

As for taxing wealth I am a huge fan of a complete estate tax and not a huge fan of income taxes. Take everything greater than $10 million of estate value when a wealthy patron dies.