[dragonwriter]

> Why not simply reducing working hours for everyone?

Because either that reduces total wages for everyone, or it makes more people permanently unemployable by raising the cost floor per unit of labor value.

Also, you can't reduce working hours for everyone, only the currently employed, and in practice reliably only the near-full-time-employed-on-hourly-wages.

> The risk of UBI is that rent-seekers might just engulf this guaranteed income by raising their prices

Not really, since UBI funded by progressive tax increases compresses post-policy incomes rather than raising them uniformly. You'd need ironclad market segmentation that survives income distribution compression to “capture” any groups increase in post-policy income, and if you have that, you can just take all of that groups income anyway, which is a problem that needs addressed independently of whether UBI is adopted.