You could ask the same question about the contestants. They solved these problems because they trained. They recognized techniques and ideas similar to other problems they encountered, and they applied them to a new problem.
But saving my information in a cookie without my consent is illegal in civilized Europe. How can they give me a personalized price if they can't keep track of who I am? At most they can use geolocation and time of day/week for a mild personalization.
Perfect timing, right after rowhammer-type attacks for GPU have been successfully demonstrated: https://thehackernews.com/2025/07/gpuhammer-new-rowhammer-attack-variant.html
There is no need for an explicit database; this problem is trivial to solve with cryptographic signatures. We already do the same thing for wireless networks, it's in the 802.11 protocol.
Of course, this only stops casual spoofers: if a three-letter agency is tracking you, they can kindly ask the Telco to give them the private key, exactly like they can ask to be included in the database.
At this point it seems people are using tabs as if they were bookmarks. What is an "unloaded tab" if not a glorified bookmark, in the end?
Maybe in the future we are going to see a shift to a UI where the two concepts are merged; exactly like in mobile OSes we don't have a separate concept for the icon of a running app.