The bigger takeaway here is that working at a large company, for any length of time, tends to sink you in (rather than lock you in) to their ways of working and it can be rather difficult to step into the wide open source world afterwards. It is not out of laziness, but out of learned ways of working and domain knowledge.
It is difficult to extricate yourself from "The <Company> way"...sometimes with panic and dismay at the sheer amount of options out there, that simply aren't as interoperable as "The <Company> way" was. This is a legitimate and valid pain point that professional software engineers, working in companies, face in their careers.
A smaller but equally important thing to note is mention of the number of people working on the build systems internally, that make and maintain interoperability between both internal and 3rd party libraries and tools, to create a smooth build system.