BI alone is by definition the poorest you can be. That's never going to be nice. It's almost certainly never going to be $45k. So long as money motivates people, people should still be motivated to have more than the poorest.

OTOH, BI does not disincentivize recipients from working, like current schemes do.

The specifics vary by place but almost everywhere unemployment benefits recede rapidly when you are.. employed. If you are disabled but manage to work part time, that can be used to invalidate your disability claim.

The whole point is to get more people working, and make it worth their while. If BI results in fewer people working, it has failed.