Well, this isn't a particularly insightful comment, but my feelings about this are "fark :[". The AVR definitely has something Nordic about it. I first learned C when programming an AVR Butterfly eval board to take photos like [0] using [1]. I've found the AVR architecture to be much cleaner than 8 or 16 bit PICs. Atmel, for the most part, embraced GPL and GCC. Microchip has tried to squirrel GCC optimization features away from being truly FOSS.
[0]: https://c1.staticflickr.com/1/53/115619170_4445c593cd_o.jpg
[1]: https://c1.staticflickr.com/1/56/112758047_dc5b4bdc3b_o.jpg