Definitely true. Also, investment in on-chip peripherals can lock companies into an architecture much longer than on higher-level platforms. We spent a lot of time debugging DMA, SPI, interrupt controllers, etc. on a micro platform and that work is not something we'd want to redo.

Basically, in embedded products you end up touching everything from the app, OS (if there is one), device drivers all the way down to the on-chip peripherals.