Cloud Database and Cloud DataLake

The term DataLake was invented to describe the data storage and the fact that after Hadoop and HDFS were introduced, you can have a cheaper way and place to store your data without using a traditional database, by traditional, I mean a RDBMS, relational database management system. Cheaper is not just about cost, it is about that you have much less efforts to just store the data. Now I see that many vendors are trying to mimic RDBMS and make the line disappear.