I definitely am not suggesting they are disappearing. Only becoming less popular.
And I wouldn't group SQLite in that list. I am assuming it has already has come from nowhere to be the most popular in use today (courtesy of iOS/Android ?) and I believe is part of an emerging trend of microdatabases.
What is happening is that SQL is becoming more popular but over the top of NoSQL systems e.g. HDFS, Cassandra.
Which is pretty nice... beyond the language of SQL, relational databases that support full ACID compliance are important for a lot of scenarios. Usually you have to sacrifice a portion of that in order to scale horizontally, or when a single system can no longer keep up.
There's been enormous progress in database reasoning the past decade or so, as more companies have needed to reach the scale of Facebook, Twitter, Google, Amazon and others... Not every instance needs that level of scale, but many businesses are also trying to reach very high levels of availability, which is an issue with similar solutions.
And I wouldn't group SQLite in that list. I am assuming it has already has come from nowhere to be the most popular in use today (courtesy of iOS/Android ?) and I believe is part of an emerging trend of microdatabases.
What is happening is that SQL is becoming more popular but over the top of NoSQL systems e.g. HDFS, Cassandra.