Anycast addresses change all the time. Ask Google, Microsoft, Amazon, Akamai, Cloudlfare and so on if you don't believe me. About the only anycast IPs that don't change are public DNS resolvers but that's also true of unicast resolvers as well.

By that logic BGP is a layer 7 load balancer since it has an application layer. BGP only exchanges layer 3 reachability information to update route tables therefore you can only load balance layer 3 with it.

Personal attacks and other things in your comments are against the HN guidelines. The goal is to talk about DNS/TTLs and their impact on performance not insult each other. https://news.ycombinator.com/newsguidelines.html