I have had Roku boxes but not thought of buying their stock. If they just end up selling their boxes or do some sort of licensing deals to integrate their software, then the range of products seem to niche. Maybe not bad as part of a company but not enough to be the entire company. It is too easy to get replaced.
NVDA actually has their own competing box to the Roku called The Shield which usually gets better recommendations though at a higher price.
https://lifehacker.com/4k-set-top-box-showdown-roku-4-vs-shi…
https://www.androidcentral.com/nvidia-shield-tv-vs-amazon-fi…
I have been using a Shield now for 2 years and never thought of going back to a Roku or AppleTV.
They are competing against AppleTV, NVDA Shield, AmazonFire, Google ChromeCast, Smart TVs and legacy BluRay players that also embed the same ability to be a media player and content streamer. Not to mention countless other media streaming devises coming out of Taiwan and China.
I am not sure I would want to hold shares in a company that’s entire product range is nothing but a blip to their competitors product ranges