I agree with you regarding the difficulty of getting Universal Basic Income (UBI) adopted in the US. Your UBET is an intriguing, plausible bridge to full UBI--which is itself a bridge to new kinds of societies based on systems of sustainable technological abundance.
Whether or not something like UBET becomes adopted in the US, it appears that Australia is moving towards trialing the MOUBI; the Market Oriented UBI circa mid-decade. It was developed by my ally Michael Haines and adopted as official policy by Basic Income Australia. They have gained the interest of the federal government. Let me know if you'd like to learn more about that.
I suspect that, if MOUBI is successful and popular in Oz later in this decade, the US may eventually adopt it. However, you and I would probably agree that the US will be amongst the last adopters within the community of advanced Western nations, not doing so until the 2030s soonest.
I fear that the 2030s will be too late for averting wrenching social disruptions. However, in my view, the US is on target for those with or without a UBI.