[Santosh83]

Because the vast majority of engineers working on the code base are employed by the management. They can't just do their own thing & remain employees. Plus the FF code is controlled by Mozilla corp. You have full freedom (as an outside contributor) only in the sense you can always fork, not that you can somehow force Mozilla to accept your patches. Same as Android and all other major OSS controlled de facto by corporations. True community led OSS is quite rare, especially among the market leading software among their category.

[dblohm7]

This is correct. Full-time devs are going to spend their work time on what the people who pay them tell them they should be working on.