Being able to create a single large product with a single programming language is a great skill, but so is being able to do Unix shell scripting.
The system/product I have been working on for the last 10 years is two major pieces that is about 90% of the total code base and lots of small pieces. The two major pieces are both essentially a single program that can be developed in unified environment. But we also have lots of small pieces that are shell scripts that are done in the classical Unix spirit.
Being able to work in both ways is a great strength for the engineers who can do that. Those who can only do one or the other are essentially marginalized as that limits what they are able to do.
This is not entirely accurate. I just heard from DDJ that an article of mine they accepted earlier this year is being published in February. I asked for one final change and told me that they could not do that because the issue had already gone to press.
Anyone can make an omelet with eggs. The trick is to make one with none.