As I mentioned in a different thread, this is an optimization thing, which we enable during heavy website traffic. While personalization will make the site less convenient to view, we believe it is a good compromise to having the site prone to unresponsiveness, or even errors. Fetching custom data is a lot more resource-consuming than offering cached elements (if I understand this correctly).
We hope you can forgive the inconvenience.

That being said, personalization has been re-enabled for the time being. :)