The article announcing Riet's resignation is https://rianrietveld.com/2018/10/09/i-have-resigned-the-word... (Working at time of writing this comment)
Automattic's position of quite verbally "throwing" Gutenberg at users and developers at any cost just shows a really bad example of business driven FOSS project as a base for commercial product (.org for .com).
A11y is just one of the victims. Other community members creating WordPress based websites, services and plugins (myself included) are mostly thrown overboard as a collateral damage. Either learn react fast and figure Gutenberg out by yourself or maybe we'll let you come back later if and when we get to work at least on some documentation and the well-known issues that affect you. With Gutenberg's extensibility being the biggest and most harming one for WP ecosystem.
Not only technical bugs, the UI is poorly designed.