So, I've been wondering about the potential party-hindering effect of magical darkness. It seems to me that, RAW, if your party members don't have a way to see through it then it's usually a wash for them: if both they and their target are inside it, both are blinded, so the advantage and disadvantage cancel. If they are inside and their target is outside, then they may even still get advantage on ranged attacks depending on whether the DM rules that magical darkness is like fog and prevents you from seeing outside of it, or whether you can still see things beyond it but they can't see you. But even if it's equivalent to fog, you're subject to both advantage and disadvantage, which cancel. And the reverse if it's the reverse.
Where it becomes a potential hindrance is if your party members would otherwise have advantage, since a single source of disadvantage removes any number of sources of advantage, or if you have caster allies that need to see to target. But the flip side also works: if they would otherwise have disadvantage, darkness removes it, and any enemy casters can't target your allies.
Then of course there's the fact that since it makes creatures inside it heavily obscured, they can hide, making their position unknown. That could cut either way. If you have a ranged rogue in the party it could allow them to pop into the darkness, hide, then pop out and attack something outside of it at advantage.
