IITB shortlists students based on their GATE cutoff score for IEOR M.Tech. Shortlisted students need to go through a written test and an interview as well for final selection. IEOR IITB GATE cutoff is 650+ for general category students.
If you want to pursue an MS from some renowned foreign university in Operations Research and Data Analysis domain, then IEOR IITB is a better choice.
If you want to work in the field of Supply Chain Management then NITIE PGDIE is a better option. The course offers cushy placements. NITIE PGDIE placements 2022 had a median CTC of around INR 19 LPA.
The selection criteria consist of an initial shortlisting based on the GATE score, followed by a written test and a personal interview.
Choosing which one is better depends on your personal preferences and interests. Nothing matters except your enthusiasm towards the course. You have to be dedicated enough or it will be nothing more than a degree.
If all you want to do is work and advance in it, you'll need to start with an excellent job opportunity. You have a better chance of acquiring such an opportunity if you study at a better and more well-known college.