Ask HN: Typed "AirPods" in notes on iPhone, 2 hours later AirPods ad on YouTube?

Coincidence.

I work in marketing technology and no such connection exists.

People are, however, predictable. It is Christmas season and you are both iPhone users. Both of you are saturated in ads for Airpods before and after it was on the list.

What other ads did you see in the same time period?

Pretty much none, maybe one or two.

Turned on YouTube two hours later, there was the ad.

Someone typed “AirPods” into google is my guess

You might not even have had to make the note

Coincidence. You have an iPhone. YouTube knows that and a bunch more about you. Also everyone gets AirPods ads.