Amirm
Did you really tried to hear the difference on Topping A90 discrete?
Oh man! This device has SMPS, there is no way to hear the difference on a device with SMPS. I hear zero difference on power cords with topping Pre90 for ex. ZERO.
But with topping d70s and my other DACs with traditional PS, there are clear differences with power cords even though D70s has great filtering and measures perfect.
And one more remark on your test. You measured resistance of the cables, for what? I think power cables make the most difference more because of their capacitance.
If you add for ex. 10pF capacitor (let say mica cap) to the power supply main filter caps it does make a difference. That 10pF with it's extremely fast discharge capability would be the "reservoir" for some sections of the device and that is heard in detail, focus, depth etc. But I am not surpriced you heard and measured zero difference with A90d that has switch mode power supply especially very modern and low noise SMPS...