Advertising is a numbers game. The goal isn’t to figure out what you want, it’s to make money. Ads are auctioned off in milliseconds to advertisers betting on what you’re likely to buy. They might know you bought something, but that information isn’t always available. They do know you looked at it though. Historically, people who look at something are more likely to buy it. Maybe you’re still shopping, changed your mind, or need another one. Doesn’t really matter as long as the numbers work out.

The UX stuff is pretty obvious. Probably comes down to the time and money involved in implementing and maintaining something better. An engineering problem. The airline stuff is likely an architecture problem. Airlines are notorious for running ancient systems (Windows XP, floppy disks). I’d bet the information is there somewhere, just scattered across a bunch of poorly integrated systems.

Like it or not, AI will probably improve a lot of this. As behavioral analysis and AI-generated customer profiles become more common, these systems will get better at figuring out what you actually want. I wouldn’t be surprised to see advertisers running small models built around individual customers and their behavior. You’ll basically just be a vector in some advertising model. The ads will probably be more relevant, but I’m not sure we’ll be thrilled about how much they know about us.