Pecona also writes in https://www.percona.com/blog/analyzing-the-heartbeat-of-the-...: "The overall trend since 2011 shows a sustained decline in the number of commits and a shrinking pool of unique contributors. The trendline is a clear warning that, without intervention, the general development pace is expected to slow further."
Oracle treats MySQL like a product line that is being kept on life support, not a community project. MariaDB feels safer because it stays active and builds in the open, so you can actually follow what is happening.