No it can't. Someone has to implement that choice. It would be visible to the technical staff.

Sure...but:

“It is difficult to get a man to understand something, when his salary depends on his not understanding it.”

Upton Sinclair

It's the opposite: without the developer understanding the thing, there can be no bug fixes nor new features, and therefore no salary.

You're focusing on the wrong, and obvious, thing.

You'll never get the developers (who are largely fungible) to fully grok the long term consequences of what they are creating because they are blinded by the (entirely natural) fact that the company is keeping them fed.

I think you’re being unnecessarily cynical and actually incorrect here. It’s not like I’m told to implement some tiny thing where the left hand doesn’t know what the right hand is doing. The entire premise of whatever system is being built is clear, as are all the discussions with the privacy folks, the execs, marketing, designers, etc. Privacy is a constant point of discussion, and often times what engineering wants is made far more difficult by privacy, and they get the final word.

If you think that you can't be duped by your employer then you've already been duped.

A single person can implement a chosen weakening, compromising everything done by lower-level staff. If you don't think this is trivially possible, you know nothing about the fragility of security.