With UBI, if you take an additional job, you would lose a large share of your income to taxes used to pay for the UBI.

Yes, you can restructure income tax levels so that people get to keep most of their additional income, and then you'd have to tax the remaining people more heavily to compensate. But if that's the solution, why don't we do that today?

This argument shows that UBI doesn't solve the incentive problem. It can only be solved by keeping welfare benefits significantly lower than minimum wages, which means lowering one or raising the other. This isn't logically impossible, but it's matter of political feasibility. That's true of UBI also.

I don't necessarily disagree. I think UBI is an important thing to study and consider as we increasingly displace workers with the ever-moving capability of tech, but it will undoubtedly have some unintended consequences.

I do think it's important to point out though that you lose unemployment if you work, so there's direct incentive there.