The main advantages of Relational database is ACID compliance. 

The common principle is if one change fails on database, the whole transaction is going to fail.

 If you have an application that the data is predictable, according to structure, size, and frequency of access, relational databases are still the best choice. 

Relational Database has a fixed schema.

 So, If your data is highly structured and requires referential integrity, its good to continue with Relational Databases. 

https://relevant.software/blog/microservices-database-management/