I'm an IT professional living in a rural area. I have found that my best option for internet access is through a Sprint mobile hotspot, which works well, even for streaming (4G LTE), but limits my data to 100 GB per month. I know from internet searches, with hits here and on reddit in particular, that other internet users would also like this feature.
The hidden screen for manually selecting bitrate seems to have worked in the past (though whether it ever did anything seems to be disputed on the internet 😉 ), but that option no longer appears to be usable, and it was never guaranteed to be working as it wasn't a supported end-user feature.
Without the ability to throttle the stream through the Roku (a feature not available via the streaming services I use directly, nor is it available in my hotspot's settings), I will see very little use for the device in the future, as it is redundant with my gaming console, where I can also install all my streaming channels.
Thanks for listening! Keep making Roku great!