> Something seems to be fundamentally wrong with an economy where we think that we need people to work in jobs that are paid so little that these people can't make a living. and it's viewed as a problem to raise their incomes.
The problem here is equating wages and income.
It is to everyone’s benefit if jobs with a net positive value get done, even if the value isn't enough to support the worker at an adequate lifestyle without supplementation.
Everyone should also have income to support an adequate lifestyle, but there's no reason that needs to come from wages — that's what a social welfare system, whether classical or UBI-based — ought to guarantee.
Say we decide $1,000/month is the minimum support level. It is generally better that a job that the market would pay $500/month gets done, the profits of owners and wages of higher level employees resulting from that job being done get paid and taxed, and the worker gets at least $500 in social support than that the job goes undone, the taxes on the other income streams dependent on it go unpaid, and the worker collects $1,000 in social support. And its even worse for the worker in the latter case if the minimum income we demand to allow work is higher than the social support we provide the able bodied without work (which is generally the case in the US, especially unless you have dependent children, outside of short-term unemployment of those who previously had sufficient income for UI to provide an adequate temporary support.)