There are certainly seismic shifts in viewer habits that have only grown in recent years, and we probably haven't seen the last of what changes that will bring. However, I think it's worth pointing out that, a lot of what CBS is doing specifically (IMO) is singular to their needs and goals. And we've been saying the same "tick-tock, tick-tock" rap about terrestrial radio, newspapers and the like...for years. They haven't completely gone away. My gut tells me that some version of that will be true of broadcast TV, for the near future, anyway.
A few years ago I predicted that as the Silent and Boomer generations age, we’ll see the true shift. And we’re starting to see it with more and more people not only cutting the cord but also watching their favorite shows on Paramount+, Peacock, etc. Not to say people don’t still watch the late-night shows at 11:35, but it’s also been a couple years since I watched a full SNL episode. Usually I’ll catch a sketch or two and Weekend Update on YouTube Sunday morning. Same for whatever Daily Show clip. I think Conan O’Brien saw what time it was when he reduced his TBS show to a half-hour.
That said, even with Wheel and J! airing on Peacock, I think we’re a good decade away from your local affiliate no longer airing them in the 7-8:00 Eastern hour, if they do at all. It’s still plenty of rural areas where OTA or cable is the way to go, and I don’t think that completely goes away. My bigger concern is what happens to local news with all the mergers and acquisitions. But that’s another question for another thread.