Like I said: Most western countries are
already paying the rough equivalent of UBI to their citizens, except inefficiently with an army of bureaucrats.
Image making $250K and paying $100K in taxes. With UBI, your taxes might go up 20% to 120K, but you get a flat $20K as your basic income, so net... there's zero difference.
If you make $500K and used to pay $220K in tax, then you now pay $264K in income tax but get $20 UBI, for a net tax of $244K. Your total after-tax income decreases from $280K to $256K, a mere 8.6% reduction in your disposable net income.
Are you saying you wouldn't get that job? It pays $256K after tax! Anywhere in the world with that kind of personal income, you're filthy rich, especially if you have a spouse that works.
Okay, so your spouse is an unemployed gold-digger. Guess what: she gets $20K UBI as well, so your family net income is back at $274K, for a mere $6K decrease over the original pre-UBI tax code.
I'm personally in more-or-less this boat, where my spouse is ineligible for all government benefits despite being a stay-at-home Mom, because I make too much money. This disincentivises educated, wealthy people from having kids!
You know who has too many kids? Poor, uneducated people for whom the per-child benefits are worth it. This produces generational poverty, not useful workers for the economy.
Disclaimer: Obviously this is using made-up numbers, any real implementation would have to be adjusted to each economy, existing tax levels, etc, etc...