Be nice everyone.
You're misinterpreting what you're seeing, though I can see where you might be lead to that conclusion. We do not artificially disadvantage any channel's based strictly on it's compatibility, though our usage metrics may weight usage on different models differently. For instance, we may sort games based on usage on Roku2 and Roku3, since these are our "gaming" products. The result would be that the order may show that those games that take advantage of Roku2's gaming features tend to be more popular on the Roku2, for obvious reasons. If a game had a lot of usage on Roku2, it would be right up there, regardless of for which platforms it was available.
The web channel store may use a different usage metric, since a large part of the web channel store is helping new users find out what's popular on the products that are currently offered for sale.
The short of it is, get more people to use your channel and it will have a better position, regardless of the platforms it supports. And reduced compatibility won't up the channel's position, just reduce its availability.