Even if astronomers wanted to, the cost of replacing all terrestrial optical telescopes by orbital ones would be astronomical. Especially if you include amateurs. Stargazing wouldn't be a thing anymore.

And illuminating all of earth? I don't want to imagine the damage that would cause to ecosystems. It would completely take away peoples' choice not to live in a place with street lighting, or even to have a vacation in such a place. Street lighting is bad enough for peoples' circadian rhythms as is.

Think about how many satellites that would require. 12,000 satellites are a joke.

The world's always changing, they just have to adapt.

Good luck living in a world without pollinators or insectivores.

That's a bit exaggerated, if illumination could kill all insects, there would not be any insects in arctic, which is false.

How many do you need to lose for the ecosystem to collapse?

Not all, and probably as little as one or two species.

> astronomers will want to use orbital telescopes anyway.

Not necessarily. With Adaptive Optics, ground based telescopes are getting incredible results. Also, they can build much larger primary mirrors on the ground than what can be lofted into space. Ground based telescopes also have the ability to be updated/upgraded/fixed/etc.