So what if Netflix doesn't work?? That is the choice of Netflix. Big content will always want more control. Firefox will never be able to keep up. They will just do a mediocre job of working against their users.
Microsoft and Real Player pushed hard for an integrated ActiveX based DRM ecosystem over a decade ago. I'm so glad that Mozilla flatly refused to entertain such idiocy. I sure wish that Mozilla still existed.
Mozilla is now just a "pick me" [1] organization to big content. They should own being a browser that caters to users, not platforms. Because they will end up with nothing.
[1]: https://www.urbandictionary.com/define.php?term=Pick%20me