Wouldn't say it's hypothetical. I'm certain stuff like this and much worse is already happening.
With the current situation (good job-market) I would certainly not continue on that project. (You know, were I smart enough to work on things like voice-detection in the first place 🙃)
I can't say how more dire circumstances would influence that, but recording voices in the background is already pretty unethical and I'd draw my line much earlier.
(I wouldn't work for ads/gambling/drugs/military.)
I already have mixed feelings about all the e-commerce-front-ends I worked on ¯_(ツ)_/¯
Good call man.
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