Pet mouses have plenty of everything and reproduce a lot if you allow them.
But from what i recall id call it more like a prison where all their needs are met and they have absolutely zero responsibilities, thus their current choices have zero impact on their future quality of life.
In people id expect that to lead to depression and mental illness which is basically what we saw in the mice. Im not convinced this experiment could be considered a utopia any more than a coed prison which also provides, food water and shelter but not entertainment or enrichment/stimulus.
Without entertainment/enrichment/stimulus even humans develop all sorts of problems like dementia, just look at nursing homes/classical assylums for the human equivalent/example.