How about getting rid of all taxes and just taxing transactions--like VAT, but more, so anytime money changes hands? 2019 was $21T, if you put a transaction tax of 30% in place, you would cover the cost of UBI.
I am normally against flat taxes because they hurt poor people, but if you're giving them UBI would this the negative impact of a non-progressive tax? You'd simplify so much but getting rid of most accountants and the IRS, drop in the bucket but nice to see. They would certainly kick and scream. You'd also collapse real estate prices because cities would lose their need, but would kickstart rural economies like woah. This would help alleviate the rural/urban friction we're currently seeing.
I'm just arm chairing, I have zero background in economics.
Why is eliminating all government services an acceptable hypothetical but not cutting any of the imperial occupation budget? I call it as such rather than the Orwellian “defense” because this is what that money is actually used for.