There are numerous issues here, I think. Firstly (but not directly relevant to the OP) is that education is not just about supplying the labour market. If a graduate doesn't use their skills, so what? We would be reverting to simply training people (presumably apart from an elite?) if all learning were simply to teach people things they 'use' in the workplace.
Re the UBI - I think it's a nice idea in theory. It might reduce the iniquities of means testing (the Devil is in the detail there), and allow anyone to choose not to work if they don't want to - particularly if a couple would get £3200 a month between them - and may work towards geographical 'levelling up' as people could move to cheaper areas to live. This would increase the prices of rents and properties in the North and reduce them in the South, so evening up life chances across the country, which would be a good thing. Also, not having to work would reduce stress and improve mental health for many, particularly young parents who are currently paying extortionate childcare and commuting costs whilst still being taxed.
In practice, though, I have doubts.
Who would do the jobs that pay less than the UBI? Robots may take over some of them, but they aren't able to do so yet, and what happens in the meantime? Why would someone work a zero hours minimum wage job if they could get the same money for not working?
Also, I can't help thinking that costs would rise in direct correlation to the income, unless there were a huge shift in our collective psychology. What would happen to money that people earn over the UBI? If that is going to be taxed to nothing, again, there is less incentive to work, so who is going to pay commuting costs, childcare and taxation to do things like nursing or teaching, which will still be needed? Similarly, who will do the work on improving the robots? Or developing medicine? Or town planning? Or all the things that will need to be done if we aren't to give over everything to robots? Will there be an 'upper class' of people who work, and a 'lower class' of people relying on UBI? If that happens, how long will the UBI stay at what is now a fairly generous level?
I'm not sure what the trial is going to prove, as the participants are living in an economy which is shored up by the fact that most people do need to work, whether they like it or not. What will happen if that need is taken away won't become clear until it happens.