One remark though:
The statistics do say nothing about popularity of a specific device, they just show numbers of downloads of certain files.
It is unknown if those downloads were done by a human owning such a device, or by a bot that does not identify himself as such.
Edit #1: If downloaded by a human, it is unknown if "1 human = 1 device = 1 download". Users may download OpenWrt images multiple times, which makes it even more difficult to deduce popularity from the download numbers.
Edit #2: Further difficulties when analyzing the download stats: 1 IP != 1 human; 1 human != 1 IP
Example:
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Therefore the old saying applies: Don't trust any statistic that you havn't forged yourself.