People would still pay taxes on income. If the taxes you pay are larger than the UBI amount then you effectively don't receive it any more, even if it's account

People would still pay taxes on income. If the taxes you pay are larger than the UBI amount then you effectively don't receive it any more, even if it's accounted in the way that you receive $1000 UBI and then pay $1000 (or $2000 or $5000) in taxes.