We probably agree on what "isomorphism" is, but maybe not "support"?
If a platform claims to support isomorphism, I expect it to render server-side with zero drama/workarounds/blog posts. Support means that producing fully-rendered html is a core part of the product and documentation, not something glued on the side or pieces to reassemble on your own.
From the wording, it looks like Aurelia isn't there yet?
Or do you mean the hint that some of the code can run server-side? That seems obvious, and is not in itself isomorphism.