Even these articles will mention that the benefits to SEO are secondary to good, relevant content that is well structured and semantic. There are downsides as well. Your ability to run paid search is limited by your domain. You can't bid for multiple positions on the same keyword with a single property. In practice, our businesses have had a much better return from the SEM benefits than the minor SEO boost.
These stylized landing pages benefit from branding, and usually aren't a tremendous amount of searchable content (I doubt anyone will ever find onehostname.com with a search engine).
I'm not too worried about Google's algorithm changes. SEO is one "free" benefit of putting everything on a single hostname, but there are lots of reasons it's desirable. You get better speed (especially with tls and http2), more control, even vanity. What we're really helping people do is manage their stuff that's scattered across 15 different services and make sure they're all delivered to end users well.
