However, the skillsets required for mustering these two concepts are different. Hence, the choice of stream should be more inclined towards the inherent skillsets and interests of the individual; as both of them are equally prosperous.
The two fields are highly related. You cannot have machine learning without data. But simple data analysis and visualization/reporting is an area which is on the decline. Also a lot of data driven models use rule based solutions. These are not scalable. Machine learning on the other hand, although being nascent, has show lot of promising results. So in future, one can say pure data science will not be as glamorous as machine learning.