Hydrophobic fungus in soil
I can't really get good photos of it, but there's some sort of mycelium in the soil of my sister's dracaena marginata that she recently got that seems to be making the soil hydrophobic, despite the top/bottom looking pretty moist. I've done some poking around online and while most people say that the fungus in here is probably a good thing, my sister is really concerned about the plant not being able to get enough water. Is there any fix to this? I've seen some things that seem to insinuate that less organic material for the fungus to break down in the potting mix might be good, but I don't think that I've seen anything concrete about it.
(And to appease the post requirements, the plant is in a south-facing window with a grow light usually. Currently it's hanging out at my home cause I am my sister's plant doctor and my sister doesn't want to worry about getting soil everywhere in her apartment in case of repotting 😅)