and many proponents are really only trying to solve for "i don't want to experience poor people" rather than "i don't want people to be poor (especially if caused by automation i created)". you see this position a lot in comments here about homelessness in SF, for example.
UBI tries to solve a complicated problem (inequity) with a simple solution (the simplicitiy of which is irresistably attractive to makers of all sorts). inequity needs to be solved by healing the thousand cuts we've endured over the last 50 years, not with the tiny little band-aid that is UBI.
we need to fix the ways that plutocrats have tilted the economy in their favor. just around taxation: income tax rates, employment taxes, capital gains tax, depreciation, corporate loss-shifting, interest deduction, nearly every deductions actually, etc. moreso, lending (student loans, mortgages), insurance (healthcare), and real estate (literal rents) have become de facto ways of extracting rents out of the many for the few.