Even if you support open borders, this technology is essential.
Given that AST's towers/software identify objects of interest to CBP, it's probably safe to assume that number is high.
I'm not convinced that a company named after a sword has good intent no matter how well their PR department tries to package it.
Border Patrol isn't out there rescuing thirsty migrants. In fact, they're known for destroying life-saving water caches and brutalizing activists who try to provide water or medical aid to people wandering that part of the desert.