What IQ loss? IQ scores have consistently increased over time

I'm afraid your knowledge is a bit out of date. Even Flynn has given talks about the "reverse Flynn effect" in the past three decades. IQ scores have been going down.

Recently: https://www.sciencedirect.com/science/article/pii/S016028962...

My suspicion on this is not the noise from the device, or even the devices themselves are the problem... It's that we sit on our ass all day watching/listening to them. Brain health is correlated to exercise and movement.

If we're talking about concentration, social media/devices likely play a _much_ larger part.

Insofar as traffic is concerned, any drop in IQ would be more likely related to PM2.5 pollution levels than noise:

https://www.nih.gov/news-events/nih-research-matters/air-pol...