India is one of few nations that can buy military equipment from both western world and Russia. When building their destroyers, India does take this advantage to install best sensors from multiple countries to their ships. However, this choosing-best-tools-for-each-problem approach is an engineering nightmare. It is extremely challenging to make sensors from Russia, Italy, France, India, etc. work smoothly together due to various compatibility issues.
The issues are not in each module itself. Essentially every large engineering project is an integration work. We can easily lose the big picture when we focus on the performance attributes of each module. So be careful next time when your architect shows you a system architecture like the below.