I think it would be good to make a distinction between UBI as an app on EOS and a UBI as a core feature of EOS.

Nobody should oppose a smartcontract which distributes its own tokens as a UBI for its users. That would be great because it would bring a lot of new users to the EOS ecosystem. Nobody would be forced to participate in it.

But UBI as a core feature of EOS is very different. It would create new EOS tokens (inflation) and distribute them to all individuals. I'm opposed to it, too, at this point. It would bring new users, so in that way it would be beneficial to EOS, but using so much resources to just one app would be very dangerous.