The comparison of bloated SPAs with lean web sites is bogus. If someone takes the effort to make their web site lean, they'd do the same with an SPA. If someone makes a slow, bloated SPA with megabytes of Javascript, they'd make a slow, bloated web site with megabytes of Javascript. I think we've all seen enough of the web to know this is true.
I click on articles like these because I've seen the effort that goes into a good SPA, and I'm interested in anything that would allow people to deliver an equivalent experience with less effort. All I see here is a tiny bit of cosmetic polish. Polish is appreciated, but this doesn't seem like something that would tip the balance between building an SPA or not. Am I missing something?