I would think if a service-oriented-architecture (SOA) were used as much as possible to modularize a project such as this to make it easier to change functional

I would think if a service-oriented-architecture (SOA) were used as much as possible to modularize a project such as this to make it easier to change functionality, was a modularized approach taken or was this just one big codebase that was essentially all lumped into one big "application"? I work on a legacy Java project that has something like 1M lines of code and its a nightmare, the team I work with is finding that modularizing pieces of it into essentially individual projects (which is seamless to the end user) helps with keeping the complexity down, just curious about this as I think the Google employee who did that rant online the other day mentioned something along these lines. I don't think the use of Java would necessarily lead to a project's downfall, I mean how are you going to scale something like this in Python if its already slow in Java?