Why is the Irms so different from Isat in different power inductors?
L at rated current is when it drops 10% of its low current value.(unless otherwise specified)
The 1st one uses a 40’C rise in temp for the normal rated DC current which must be debated for AC current.
L at saturation current is when it turns into a resistor of DCR value (290 uOhms) and much smaller inductance.  I know, 70nH is small already but the ferrite core is unable to store much energy at this level, so it must have a very soft corner on the BH curve.
The second one has a 20’C rise at 56A , 20% drop at 65A and a 40’C rise at 74A.
So they defined saturation by a 20% drop in L which is about a 30’C rise in temp.
Thus the 2nd one is much better (74A vs 55A dc not RMS) as the current rating is higher for a 40’C rise.
How much to degrade for AC rms is another question that depends on your current spectrum and SRF.
Final remarks
It’s all in the fine print and it’s easy to confuse apples and oranges for rms and DC current and temp rise vs Drop in L.
The one with the lower DCR might seem to be better but core loss can cause temp rise as well as wire resistance in this case it is rated at DC and not at ACrms in one. Here the one with the Lower DCR is better. 130uOhm DCR on the Coilcraft is better than the Eaton one with 320uOhm DCR. It also has much better SRF.
For SRF it is not clock rate that matters but the 3dB BW must be much lower or f(BW) = 0.35/Tr (10 to 90%)
But beware that SMPS with very low DCR and low ESR and Ron has very high Q which can cause overshoot on a step response, so slope compensation is essential.