UBI is an inevitability. You can argue over whether or not now is the time, but rest assured the time
will come. Human labor will become almost entirely obsolete in the centuries to come.
"Somebody will have to repair the robots."
Robot repair work will not make up for the millions of jobs lost to automation, especially when robotics becomes so advanced that humans can't even work on them anymore. The robots will be doing that too. Once the jobs dry up we can either have UBI or let society collapse. Something tells me we'll choose the former.