There is no objective evidence to support any of these claims. In order to see an object clearly, light passing through all parts of the pupil of the eye must be focussed to converge on a single point on the retina. If the light is not accurately focussed, it will fall on a circular region on the retina, rather than a single point, and the object will appear blurred. Pinhole spectacles substitute a pinhole with a diameter of around 0.7 mm for the eye's normal pupil, which typically has a diameter of 3 to 4 mm. This does not alter the focus of the eye, but reduces the size of the blur circles to the extent that reasonably clear vision is obtained.
Vision is blurred.
Myopic eye with pinhole. The pinhole reduces the size of the blur circle, but vision is still blurred. Myopic eye with lens correction. The image is focussed clearly on the retina. Pinhole spectacles have been used by optometrists and ophthalmologists for hundreds of years.