Most buzzwords exist for consultants to sell their services. Successful buzzwords turn engineers into "Big Data Engineers" who only want to work on something called big data, and convince management that they need more "big data expertise".

In practice most of these technologies and their peers exist to support real applications, and it would be almost immediately recognizable that they are the appropriate choice when working on a similar application. You don't need a streaming engineer/big data consultant to cram them in.