This is so wrongheaded that I’m actually wondering if this story was pitched by some group that wants to smear geoengineering. I mean, geoengineering has a lot of ideas in it that are (while still out there) much less viscerally horrifying than blotting out the sun.
It seems possible to me, although definitely not certain.
The worst consequence would be less photosynthesis and less food, but we have surplus food production capacity on Earth. And maybe even that could be avoided if the blocking happens mostly in the infrared regime that causes most of the heating.
On our current path, we have areas of the Earth holding hundreds of millions of people which are projected to become too hot for human life for some of the year. Action that avoids that has something going for it, even if it also has downsides.
What a double standard you have.
There are far larger changes in insolation over the day and over seasons. Life is obviously less sensitive to these flucuations, than life would be to changes in temperature.
One goes from 1000 W/m^2 in noon sun to, what, milliwatts/m^2 from starlight? Many orders of magnitude. Temperature goes from maybe 250K to 320K over the year, maybe, a change of maybe 30%?