The issue with ubi is that it will never be implimentable with the type of winner-takes-all government of the US, UK, Australia etc. There will always be a slim majority to cross out the Universal part and give people like them (almost) double and everyone else nothing. This is why we have insanely high pensioner benefits and no funding for working people at the moment.

If you cannot implimented a good policy, it doesn't matter how good it is, it's a unicorn.