You don't expect anyone from Roku to answer that, do you? 🙂 But of course they're ad revenue related! It appears to be all they're interested in anymore. It's a way to try to drive users to content they make money off of.
As far as the 3 vs. 4, only a very low percentage of guinea pigs... I mean users... ever saw that option. My gut feeling is that it may return for everyone (especially if they can add more ads), but don't ever expect Roku to do anything quickly.
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