I don’t think many people would choose not to work- both for the reasons you listed and because a UBI, at least one we could afford any time soon, probably wouldn’t be enough to live off of. Instead, the real choice would be between working longer/shorter hours.
A UBI that isn’t sufficient to allow one to live with some dignity is not worth doing. Anything short of that only provides employers with more subsidies and reason not to pay employees, instead, satisfying unreasonable expectations in the investment class and upper management. Affordability is never an issue for the issuer of a fiat currency.
AI will, sooner than we might want to think about, make employment obsolete. In many ways the functions of corporate management may be better accomplished by a computer as most are simply decisions about capital allocation and planning. We’ve had systems doing that for some time in a slightly different context of war games in the military. At that time meritocracy will also become obsolete and everyone’s job will be “consumer”.