No it doesn't. You haven't explained where you got your numbers but those numbers are presumably for a household rather than an individual (which would then receive more than one basic income) or some atypical edge case where a person qualifies for an uncharacteristically large collection of benefits.
A basic income is a pure redistributive program. It can't possibly cost more than a program which is more redistributive than it is because there is nowhere else for the rest of the money to go.
> And that's ignoring taxes needed to fund a functioning government - e.g. roads, law enforcement, blowing up Afghani weddings, etc.
All of that other than the military costs a comparatively small amount of money. And we could probably stand to blow up not so many weddings as we do.
> (Incidentally corporate taxes are just taxes on people, merely hidden from view.)
That doesn't mean including it wouldn't reduce the rate. US GDP is $16.7T. Total US personal income from above was $8.9T. That's quite a difference. An economy-wide flat tax would require a rate of ~14.7% for $10,000 per adult and ~29.3% for your unrealistically high $20,000.
And keep in mind that that is the marginal rate. The effective rate under a basic income is lower than that for everyone. If you make $60,000 and pay 15% but get a $10,000 basic income then your effective tax rate is negative, as it is at a 30% rate and $20,000.
And that's ignoring taxes needed to fund a functioning government - e.g. roads, law enforcement, blowing up Afghani weddings, etc. So 65-70% flat tax rates? Or just a 37-42% tax rate, plus we've cut wealth transfers in half? Concretely, which one are you proposing?
(Incidentally corporate taxes are just taxes on people, merely hidden from view.)