The problem with having too many eternal branches is that they quickly become unmergeable. The nice thing about feature branches is that it's the author's responsibility to make it mergeable. But if you having a bunch of eternal branches none of which are "owned" by one person, when it comes time to merge them and there's dozens of merge conflicts there's not one person that can set down and know what the correct fix is for all of them.
I think the idea is that the branches cascade. You would never create new commits directly into release or master, the flow would only ever be develop > release > master, thus making merge commits and conflicts impossible.
That's exactly what hotfixes are for. A completed hotfix will merge directly into develop and master simultaneously (practically speaking). This allows you to keep your unrelated develop commits out of the master until you're ready to merge it all.
