Leave the Apple ecosystem? Probably not. Stop subscribing to Apple TV Plus and stop using the Apple TV app page, most definitely. For now (since I'm stuck with the beta) I'll launch to the app screen going forward to limit my exposure. That said, I was using Apple TV because it was marginally better than the alternatives and now it is marginally worse.
People compare this latest ad-focused UI update to other companies and their interfaces, but there is a giant caveat. Google products like Chromecast w/ Google TV show me exactly what I was planning on watching anyway. It's creepy and intrusive, but the recommendation system works. The Apple TV app always recommends shows I do not intend to watch. You couldn't pay me to watch Shantaram, yet it takes up 98% of my screen right now and it's been the same recommendation since that show launched. Every. Single. Day.
So if I'm going to be stuck with an intrusive recommendation system, I might as well go with one that is significantly cheaper and works. Obviously, this is a personal decision and is based on individual tolerances to ad tracking, etc.
To each their own, but for the love of God Apple - Just let me have "Up Next" on my home screen at launch.