hi,

see specialization course does not debarred you from not selected for CSE related job, while you go for specialization, that means you have studied the particular topic apart your generalized syllabus. however if you want you may go for others relevant streams job as well. after completing b.tech in cse you may apply as software engineer, programmer, data analyst , web developer like positions. however big data/ data science or cyber security each of the technology has wide opportunity and chances that it would increase in future. however apart from stream you have to be very selective about college and placement record so that you do not need to struggle for job after completing the graduation.

hope you understand.

No there are no possibility of getting reduced probability for Jobs. I would say that Data or Big Data is the best possible for any student because Data science management and Big data analytics is the most demanded field in present scenario as well as will increase with time. So if you can I would recommend you to take the Data science or Big Data specialization for a better future prospect.

I hope my answer helps. All the very best for your future endeavors!