Totally agree with the article, Justin.

Building a theme-specific blog plugin (or any kind of theme-specific plugin) will flood the WordPress.org with them. They make the theme-plugin separation useless, and thus the presentation-functionality separation useless.

Instead of building such block plugins, theme authors should try to leverage the available blocks in Gutenberg to do useful things, such as adding block styles.

I have an useful case of using Gutenberg blocks: we make a small plugin called eRocket that use Gutenberg social blocks to create a contact widget (which shows social profile links) and social sharing buttons. I think it's better to stand on the shoulder of Gutenberg to build things instead of adding more similar things to it.