Wait, they're not letting you stream because of your OS? That's bullshit, I'd pirate it on principal at that point.
No sense in waisting time trying to get your browser to report a different OS to work around it.
Using Linux means DRM protected content either plays in terrible quality or in RakutenTV's case not at all. Netflix is limited to 720p with low bitrate and Amazon limits to ~540p.
Changing user agent doesn't work because it's the DRM who decides whether the OS is supported.
Linux users have to decide between low quality legal streaming services, or piracy with high quality. It's not a difficult decision for me and my giant HDD.
Edit: I forgot the third option: streaming sticks (Roku, FireTV).
a funny thing that I'd like to add, is that pirate streaming sites don't have this limitation. You just open a website, write in a name, and play in on any platform, with good enough quality, free from all streaming services. Piracy is just too good to be true.
Roku is really locked down, which allows them to control what users can do. This means DRM is more powerful on Roku Linux, than on desktop Linux. Same is true for Android. Not allowing Linux makes sense from the rightholders standpoint (just like it makes sense for me to pirate).
I'd honestly prefer this than to what Netflix does: Don't warn you at all but then limit you to 480p or whatever. Now THAT is some bullshit. But hey, at least this way no one will ever be able to pirate 4k shows off Netflix, right? RIGHT?
I didn't subscribed to it either and never will. My father received a coupon for a free movie and watched it. I then tried to log in on my pc and this happened so... ̿ \(͡ ° ͜ʖ ͡ °)/ ̿