1) I don’t think implicitly arguing that wireless mics should switch to spread spectrum will advance the white space cause. Comes across as a bait (no interference to legacy systems!) and switch (legacy systems must change!).
2) I think you can get very close to what Google wants with pseudo-noise codes or fast frequency hoppers as opposed to adaptive codes which could have some significant stability issues with 300+ uncoordinated adapting mics all in close vicinity unless done right.
3) I do think it would be a good thing to use digital spread spectrum mics instead of analog mics, but Google (and this applies to me as well) is the wrong one to be making the case. Because of the messenger, it’ll likely slow the transition.