Forced to implement is the wrong term - they were tasked with designing it. They can't just swap one person out for another - losing the lead dev or designer would be delay or kill the effort
They could've pushed back - software ethics is a required course for very good reason - but it's easy to never ask if you should do something and skip straight to how. It gets easier to skip that piece every time, and the company isn't going to respect it - we need outside pressure so they can point to us and say "this will have repercussions"
They don't deserve death threats, but trashing everything they push on GitHub is fair. Measured steady pressure - save the most extreme stuff for upper management and shareholders
For the engineers you have to make them understand they did bad and they should feel bad, they need to feel that their peers have lost respect for them, not that this is the public lashing out