Good points. But lens building is a complex endeavour that requires tooling at the manufacturing level (especially computing power!) - no matter the choice of a

Good points. But lens building is a complex endeavour that requires tooling at the manufacturing level (especially computing power!) - no matter the choice of available material, yes? Doing it with high precision at a civilisation-powering scale seems like an impossible ask of a species that was still considering much of their Home planet to be “new” (Americas).