Not to be dismissive but you can write software for a living and not deal with personal data. It's possible. Entire fields out there.
Highly sensitive personal information like medical records are of course easier to ignore.
It's not only about which data goes trough your system. It's about what you do with it.
When I go to my friend's house they also see my face and hear my voice, but they don't record it. That's an important distinction when it comes to privacy.
Which is pretty much any non-toy system, and a bunch of toy systems.
And you’d be surprised how many friends are recording, especially if they have kids - nanny cams, home security cameras, ring/doorbell cameras, etc.
It’s probably 50% or more of households now.
It doesn’t require that they’ve got a mic taped to their chest to be doing so.