You didnt mention your firmware version (Settings/System/About).
I notice you didnt show a pic of the Roku Network information screen showing the actual detected internet download speed using Roku's "Check connection" function, either using wired or wireless.
(When you run "Check connection", it then lists the detected download speed in the information)
Why are you not running Roku's speed test and showing its results?
Regardless, try changing the 5Ghz channel or changing the channel width settings on your router, and testing again (use Check connection).
You should also check using 2.4Ghz (if you dont have separate SSIDs for each range, I highly recommend doing so).