Weather they opt for the lower end denominator still means you get greater benefits playing old games on the Series X. Much like how a good PC will run games good compared to a average PC running games averagly.
Gears 5 running at PC settings is a perfect example. Imagine if all 1st party Xbox games get next gen boosts like Halo 5 running with Ray Tracing at a constant 60/4k? That game already looks amazing on the X1X.
They only get the "boost" if the developer codes for it - that's the tricky part, which is why I hate the concept of dividing a userbase with different hardware configurations.
Again - I could be totally wrong about this. I'm certainly not claiming to be the expert as to what's going on with the upcoming generation. I'm basing my opinion solely on assumptions built upon how things have been done in the past.
...but putting all this aside, I think @NobleTeam360 hits the nail on the head - I honestly don't like ANY of these prices, and I'm not sure I'm willing to shell out the money required to get into this next generation until those prices come down.