There is a difference between mirror like reflection and diffuse reflection. Mirror reflection is what you get with metal roofs which beam the sun directly to a target resulting in one spot being blinded. Diffuse reflection will spread it around, resulting in more light all around which is what we can handle as humans.

The title is misleading from what it actually stated in the article.

It seems that it is mostly aimed at persons who are missing teeth that did not grow at all. By giving this medicine they would have more of the teeth most people have.

The title would suggest that it would allow growing teeth back that have been lost. This could theoretically be a further extent of this research, but it is not what the article seems to describe.

In cities yes. It still is unparalleled for renting small holiday homes in “rural” areas. E.g. Scottish Highlands, French Brittany.

That is the proper use case, where you would otherwise book an other B&B.