I'm not a lawyer either... but I was a ham. The issue is Part 15 type acceptance. In the case of a software-controlled radio, the firmware that controls the card would be part of the type-accepted unit -- and whatever part of that might run on the host PC would thereby *also* be part of it.
No, this is not authoritative with citations, either, but hopefully, it at least clarifies what people are asserting is the issue.
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