[michaelt]

I assume most people working in these industries think the stuff they're working on is fine (or at least represents a benefit to the world on balance) but they choose not to debate this stuff online.

They probably think (a) there's a risk of embarrassing their employer, as such companies often rely on nuanced arguments to justify their actions; (b) they're unlikely to convince anyone, let alone change the community's collective opinion; and (c) they're likely to garner downvotes and similar expressions of disapproval.