Humans need jobs in order to be able to pay for things and keep the economy running. AI is going to cause job loss on a scale we've never seen before. These people are not going to simply retrain into a new career and find new jobs. Those hypothetical new jobs are soon going to be automated away as well.
The economy and how we view income generation needs be rethought entirely. We're headed towards a society where most people will not be working meaningful jobs, if they have jobs at all.