I am not an expert, this is my opinion based on casual observation and some experience with the death-roll that one encounters in maintaining a wifi-based Linux machine, but the 'reason for this', for those asking, or "why is this needed?", is this: because there isn't an open source stack all the way from http:// to wifi0:, all the way, for a lot of the available chipsets. Wifi radios are little ARM machines surrounded by a black box, which somewhere depends on a binary blob to do the radio control/communication. So I think the answer is that the
radio is where the open-source is needed; everything else is just a Distro War/-solution.
tldr; consumer wifi stacks that allow open network bonding/pairing/ad-hoc connections, are dependent on the vendor-provided firmware blob having control over these features at the radio level. Thus, we need a fully open radio component to be truly, 'safe'.
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