Why is there such a glut of doughnut peaches?

[BlackAmericanoNoSugar]

They used to be quite expensive a few years ago, but now they're much cheaper than regular peaches. My local supermarket has been offering a punnet (about 6 peaches) for €1 for most of the summer. They're not substandard at all, they taste great, they're just really, really cheap.

Maybe more people grow them now so the price falls.

I was thinking that. When they first came out they were more expensive than regular peaches so perhaps loads and loads of farmers planted the trees then, and now those trees are in the mature stage.