I think it's normal to have a hard time delineating between conspiracy and genuine concern when it comes to this. We're literally carrying around powerful computers with exceptionally reliable connectivity combined with high-resolution cameras and high-fidelity microphones that are frequently used for voice recognition. Not to mention that for 50% of US smartphones, the software is designed by the most prolific advertiser in the world.
I had an experience a few years ago where I had talked about a fairly niche product (I can't recall exactly what it was) and the next day I started seeing ads for that product all over the place. I commented about it to two of my coworkers that day, how I had been skeptical about the conspiracy that our phones were listening to us for marketing purposes but that this felt eerie. What shocked me was their response: They had seen the same ad all over the place. Since then I've had a hard time deciding what to be more concerned about: That my phone might be listening, or that I might have been subtly influenced into thinking about this thing; that my whole experience was actually a result of being susceptible to marketing directed at my demographic
I had an experience a few years ago where I had talked about a fairly niche product (I can't recall exactly what it was) and the next day I started seeing ads for that product all over the place. I commented about it to two of my coworkers that day, how I had been skeptical about the conspiracy that our phones were listening to us for marketing purposes but that this felt eerie. What shocked me was their response: They had seen the same ad all over the place. Since then I've had a hard time deciding what to be more concerned about: That my phone might be listening, or that I might have been subtly influenced into thinking about this thing; that my whole experience was actually a result of being susceptible to marketing directed at my demographic