What's the deal with the compatibility between Spectrum TV app and streaming boxes?

I've been a Spectrum customer for years and was usually satisfied. Not anymore. We've went through 3 different streaming boxes (not a Xumo fan, at all) because NOT ONE would work seamlessly with the Spectrum TV app. Constant loading, crashes, error messages, numerous network reboots, login and out a thousand times…We bought the Cadillac of TVs and the Roku Ultra is the best streaming box on the market. Too bad Spectrum won't work with it. I'm convinced Spectrum makes it where you HAVE TO use their Xumo for a trouble-free, 100% compatible experience. I've had to settle for Apple TV 4K box (I'm an Apple guy but Roku Ultra is even better and what I want and should be able to use) because it works better than the others, and it still takes forever to load the Spectrum TV app. Had a Tech last Friday tell me he's had this same call more times than he can count, and it's all on Spectrum's end. Roku Techs hear from Spectrum customers often about the same issues: constant loading, errors, crashes, logging in and out a thousand times, reboots, resets, uninstalls/reinstalls…you name it. I'm seriously starting to think Spectrum is basically forcing us to use Xumo or suffer the consequences. To not be able to use a Roku Ultra box, when Spectrum is fully aware of the issue, and Roku is, too, is crazy. Xumo needs a complete overhaul, U.I.-focused, or a Premium box to use with Premium TVs. I'm not gonna get into the whole "when's the fiber rolling out" to some rural areas… C'mon Spectrum! Get the kinks out where we can use the streaming box we want to use and/or create a Premium Xumo box. Focus on what your customers tell you they want, not what you think we want, because this ain't it.