Linux provides an amazing suite of functionality for embedded systems, and it is hard to overstate the benefits of using such a feature rich and well tested base. This functionality comes at a price however, as when compared to non-Linux systems it generally means increased complexity, binary size, and more often than not startup time.
Embedded systems often require one-off development fixtures to help support the development process. Made ad-hoc by hand, these fixtures are often fragile and can take valuable engineering time away from other important tasks. Changes to the PCB manufacturing ecosystem means creating and handling these fixtures doesn't need to be as painful, costly or as time consuming as it has been in the past.
