That said, it is very rare that I hear someone describing themselves as Christian who denies the general 7 day creation story. I happen to personally believe it was seven consecutive days^, but I've heard arguments it could have been seven days with an unknown gap in-between each pair.
^ "day" being the most morally-understandable way of describing the intervals at which the creation occurred. Obviously there was no sun or even light at first, so the concept of a day itself is shaky, and I make no claims as to how many cesium-133 transitions may have occurred in that period, or how far light might have travelled in one of them once it was created, or the magnitude of the various fundamental forces' impact on matter in that period, or really anything related to our understanding of how the dynamics we currently observe may have behaved in those intervals.
But how much of the world's resources have been dominated by folks placing their faith in Eru Ilúvatar?
And I'm sure you're aware Tolkien was a devout Catholic, and described his works as fundamentally Catholic?
We can certainly say that the observations look like they may have progressed at the rate we expect for the past 13 billion years, but that does nothing to exclude the possibility that around 6,000 years ago some actor we do not understand took 1 week to craft everything we observe now to be precisely how it is.
Reading your final paragraph, I believe we are more aligned than I previously thought. :)