I get the impression dlang is mistaking us for someone else.
I don't know of any member of FSFLA having ever told any vendor to put the non-Free Software in flash.
Quite the opposite, we encourage the vendor to do so, and release the firmware as Free Software. Then, the freedom #1, to study the source code and adapt the software to one's own needs, is not rendered useless by the fact that one cannot possibly install a modified version on ROM.
If it's in modifyable memory, this changes a lot to me. But you might get different answers if you ask others.