Which SoM product line would you say has the best vendor support? I'm talking about quality of the BSP (board support package). (A meta-layer, in Yocto terms.)
Raspberry Pi has quite a community behind it, so meta-raspberrypi has a number of contributors. (None of which payed by the Raspberry Pi foundation, though.)
My latest project involved a NVidia Jetson SoM, and I was surprised to learn that the BSP doesn't see any support from NVidia at all. They rely on one motivated guy (Matt Madison) maintaining it in his free time.
I'd love to see a vendor that provides a first-class BSP maintained by their own people.