Aren't most Linux drivers closed source binary blobs?
See https://en.wikipedia.org/wiki/Comparison_of_open-source_wire...
The driver layer (code around firmware that initializes the hardware and marshals/unmarshals comms to/from the device).tends to be GPL lest it taint the kernel. The firmware on the other hand, is the last unconquered vestige of the Open Source landscape. Logic locking, and the prevalence/nature of fabless semiconductor IP tends to make that endeavor incredibly difficult.
It is really hard to have a complete personal computer on Linux or any other OS that doesn't require closed source / proprietary binary blobs.
Now I run OpenBSD, and I could purge /etc/firmware with no issues if I wanted.