I responded to this here (https://news.ycombinator.com/item?id=45471337) but I want to emphasize this: your domain is "just" a handle. If something happens to it, you still control your identity, so you can point it at a different domain. Apps just display "invalid handle" instead of your handle but your posts/follows/data stay intact. You can go through a "change handle" flow then and fix it.
Unlike with web redirects, you don't need cooperation from whoever owns the old domain because it's the DID Document that controls which handle you use, and you still control the DID Document even if you lose your handle. (That's part of what my article tried to explain by showing the flow: domain is resolved to DID, DID is resolved to hosting, links are stored with the DID.)
When you change your handle, all your followers/posts/etc stay with you, it just seamlessly updates in the apps you use.
Unlike with web redirects, you don't need cooperation from whoever owns the old domain because it's the DID Document that controls which handle you use, and you still control the DID Document even if you lose your handle. (That's part of what my article tried to explain by showing the flow: domain is resolved to DID, DID is resolved to hosting, links are stored with the DID.)
When you change your handle, all your followers/posts/etc stay with you, it just seamlessly updates in the apps you use.