From Oracle GoldenGate 18c onwards, Classic Extract for Oracle Database was deprecated and from Oracle GoldenGate 21c onwards, the Classic Architecture itself is deprecated. Not only for Oracle Database, but also for Heterogeneous Databases and BigData Adapters.
From Oracle GoldenGate 21c, Microservices Architecture is available for Heterogeneous Databases and BigData Adapters.
Let us see in detail.
Classic Extract from OGG 18c was deprecated, but from OGG 21c it is completely desupported. So, Oracle GoldenGate for Oracle Database does not support Classic Extract from OGG 21c.
Like wise, Oracle is slowly removing out Classic Architecture, not only for Oracle Database, but also for Heterogeneous databases.
Oracle GoldenGate Classic Architecture is deprecated for the below databases,
Also, the Classic Architecture is deprecated for BigData Adapters
This is the beginning and slowly, the entire Classic Architecture itself will be desupported or even unavailable in future releases.
Microservices Architecture is the future and Oracle is pushing the customers to migrate to Microservices Architecture.
If you see in the Oracle downloads, there is an additional binary for all the above mentioned databases and BigData which is nothing but they are all Microservices.
In the above image, we could see that Microservices Architecture is released for BigData as well.
To know more about Mircroservices Architecture, check the below link,
Oracle GoldenGate Microservices Architecture