Like the post above says that there are multiple issues at play with AI. The same can be said about universal income.

The pay levels are not comparable because you are also recompensed with time. You may choose to spend your time in a number of ways that you find rewarding that also reduce your expenses. Making your own meals, clothes, furniture, beer, wine etc. There are a lot of people who would enjoy doing these things but are too time poor to do so.

Your expenses also reduce by the amount you must spend in order to make yourself available to work. Travel, work clothes, medical certificates when sick. You can spend a lot in order to be paid.

If you want a world with a reasonable distribution of income levels. It stands to reason that those receiving more right now should receive less. Certainly, the absolute wealthiest should reduce the most, but on a global scale, it is hard to defend that those in the top 10% of incomes should retain their position.

The proposal for how much a universal income should pay is a variable to be argued itself. I can certainly see it being argued for at a lower level than ultimately desired since something is better than none.

In a sense the end state of a universal income in an equitable world would be remarkably simple. The income available divided by the world's population,

Those reviving more than their share now may not be happy about it, but I'm not sure they have a right to their larger portion either.