Basically, SPA frameworks are useful when you are working with lots and lots of data moving back and forth. A good example is something like Intercom.io's interface. They have tons of tables and modals and data flying around. This isn't conducive to the standard browser request -> server render -> load whole new page on the client. It's just too slow. When you're interacting purely with data in a master interface, SPA frameworks are the way to go. And it isn't even a matter of literal page loading and rendering speed, it's the fact that refreshing the view with a whole new page on each link click is a context change that adds up when you're managing a lot of data or performing a lot of small tasks in an application.

But something like Blogger, where you're reading just some content, maybe some comments...there's no real benefit from loading it in a SPA environment. Render it server side, cache it, and fire it to my browser as fast as possible.