I don't understand how Microsoft handle's Xbox backwards compatibility on the Series S/X, but under the hood there are clearly stubs to trampoline original expe

I don't understand how Microsoft handle's Xbox backwards compatibility on the Series S/X, but under the hood there are clearly stubs to trampoline original expected behaviors to unsupported dialog messages. Some legacy games appear to not support split-screen anymore, as far as I can tell from the store pages of specific Xbox 360-era games. All-in-all, it's a subpar experience that I think will only continue to be disappointing, and the only real solution is to find used hardware and play the games in the manner they were originally designed. Anything off the digital stores will be subject to alteration, sometimes just because they can, it seems.