I don’t see anything abnormal about the base of the stalks.

The pots are far too large, and the soil looks far to heavy and full of organic matter. If they were mine I would downpot them into a proper succulent mix.

They should not be white on the bottom of the stem and leaves should not be turning brown. You don't see that?

White is lack of sunlight and brown is overwatering or sunburn but here it looks like overwatering. Aloes like a gritty mix — do away with peat mixes, that mix looks too rich for succulents and the pots are waaaaaay too large for those plants. i would go with something half that size at the very least