https://www.manton.org/2018/10/23/wordpresss-gutenberg-vs.ht...
https://www.manton.org/2018/10/23/wordpresss-gutenberg-vs.ht...
There are as many sites still on Magento 1 as 2 which they would want to avoid.
And I suspect this is the case with quite a few recent WordPress changes to be honest. The people behind it don't want to be seen as the folks making the 'beginner' or 'amateur' CMS, they want to be up with the 'cool' kids working for Google/Facebook/Netflix/Airbnb/whatever with React and Vue and Angular and what not. For them, stuff like Gutenberg (and arguably even the REST API) feel like attempts to move WordPress away from the 'CRUD sites for small businesses and non programmers' market to the 'professional' one.
Yet that's exactly where the market is for WordPress, and that ease of use that attracted beginners and lower end agencies is why WordPress got so popular in the first place. You didn't need a lot of experience with frameworks and build processes and MVC structures and what not to get started, you could just copy or hack together some simple code to get things the way you wanted, and use third party themes/plugins to do the rest.
Trying to make things more complicated or move the core of the system over to a JavaScript framework basis (as some suspect Automattic may be trying to do) will just kill a large part of the WordPress community, and remove the ease of use aspect that makes it so popular at all.