To anyone thinking that 18m² isn't that big for how large the space is, please recall how bright reflective things shine during the day when you hit the right angle.
To give an easy visualization for most people (average Americans, really, because most other people in the world already know what a meter looks like), imagine that the average doorknob is about 1m above the floor, so imagine basically the bottom part of a typical interior door is about 1m sq. Now, make a square out of 18 of those pieces wide by 18 pieces high.
Except for those few of us who grew up interested in science, because science pretty much world-wide (even in the USA) uses metric for pretty near everything. I've used metric for my entire life, and been ridiculed for it that entire time by all the same morons that think any interest in science makes you a "nerd" even if you also happen to play and enjoy sports (despite almost the entire rest of the world standardizing on metric long ago), and despite the fact that most folks in the USA are already using metric themselves every single day. Yet somehow metric is "too hard to learn, waaah!" (It's based on tens, just like our money. Too complicated? Gimme a break!) Hell, our sugary fizzy drinks even all come in 1 and 2 liter bottles, FFS!
A gigantic source of light in the sky that lights up a part of the Earth and is too bright to look at is... the sun. I think we're all used to the sun.
What do you think is being proposed, exactly? Some sort of alternative sun that's going to shine on the entire earth, that we'll all be forced to look at?
No. I used a rhetorical device to highlight a theoretical monopoly we assume would never exist. But imagine I launch a space sail that can cast a shadow on any part of earth I chose. I could block or unblock sunlight at will and grant access only for paying customers.