No shit, Sherlock. Of course, all of this was obvious to any of us with more than 5 minutes of industry experience, alas this field seems super prone to reinventing the same things over and over again, making the same mistakes and never learning from the past.

Also, this article does not even mention the fact that SPAs are terrible for SEO. Of course, that's not an issue for YouTube, but it might be a huge issue for your clients, unless it's ok to not have any search traffic.