It isn't so much about controlling how you watch it as controlling what's produced to watch or read. As for "you can just stream it" let's see, Disney owns at least 30% of HULU, NBCUniversal through Fandago purchased VUDU,along with having Peacock, ViacomCBS own PlutoTv, Amazon of course owns Amazon media(licensed & original movies,tv). Remember that NBCUniversal is owned by Comcast. Poor Netflx is like "Why people want to jump me for a rate hike?"
"On February 25, 2020, Comcast announced it would purchase Xumo from the Panasonic/Viant joint venture for an undisclosed sum. The acquisition of the service—which will continue to operate as an independent business, albeit within Comcast's cable television division—stems mainly from Xumo's partnerships with smart TV manufacturers (including LG, Panasonic, and Vizio), which would allow Comcast to use Xumo's placement to market or showcase Xfinity and other Comcast services as well as use its technology to develop additional streaming platforms. The company plans to add content from the NBCUniversal programming library and the company's various television networks as well as use it to upsell its free/subscription hybrid service Peacock, akin to ViacomCBS's utilization of Pluto TV to offer content from its cable networks following the former Viacom's purchase of the rival streamer in the Spring of 2019."
They control what we can see......