As I understand it, inflation was proposed to provide a mechanism by which now-causally disconnected regions of the universe could have once been in causal contact, and thus explain correlations in CMB temperatures between regions that shouldn’t have had the ability to exchange information.
My question is simple: Why not instead propose that the initial conditions were sufficiently the same in distant regions to result in similar temperatures in areas not causally connected?
Forgive my ugly analogy:
If I find 2 coffee mugs in a house, one on the first floor and one on the second floor, and they are both exactly 200 degrees F, I can propose either that:
A) These mugs have once in the past been in causal contact, and thus had time to equalize their temperatures
B) Both mugs were exposed to sufficiently similar conditions to result in similar temperatures.
In this case, my microwave.
The latter seems by far the better choice; why have we settled on Choice A to explain CMB temperature correlations instead?