The reason why Node.js cuts down on development times is due to the fact that you can have the same engineers working on both the frontend and backend - Basically it puts you in a situation where you can have a single engineer own a feature's development end-to-end.
When you have a company which is split up between frontend and backend teams, this requires your engineers to coordinate their work with one another and this reduces overall productivity (you usually need a lot of back-and-forth to bring the feature to completion).
When you have a company which is split up between frontend and backend teams, this requires your engineers to coordinate their work with one another and this reduces overall productivity (you usually need a lot of back-and-forth to bring the feature to completion).