Gnolls are hyenas corrupted by the demon Yeenoghu and are cursed with an undying hunger. They are literally ravenous, and when you have an uncontrollable primal instinct like that, you’re going to act crazy. You’re not going to maintain a very strong social structure. What the gnolls have is a loose tribal structure with a medicine man-like religious leader and a pack leader. They can be either male or female, doesn’t matter, it’s whomever is in that position. They raid and ravage the wilds, looking for food to sate their hunger. This has been a part of D&D lore long before 5e, so it’s not just an issue with a particular edition.
Comparing them to how hyenas really behave is also not going to work, because they are more evolved and developed than hyenas, so they are going to have a different social structure. Also, their corrupted nature is going to warp everything about them, from behavior, social structure, language, so those criticisms are not really going to hold up, due to how differently they diverge from the very animals they come from. Hell, even gnolls in World of Warcraft behave in the same manner as those from D&D. Why should humans behave in a similar manner as gorillas or chimpanzees? We don’t, because we are more intelligent than they are, and our social structure is going to be more complex. Same can be said for gnolls.
Gnolls are considered humanoid because of: 1. the gnoll physiology of them being on 2 legs 2. having a social structure 3. having a spoken language. Alternatively, you could classify them as an aberration or monstrosity, given their origins. But their classification shouldn’t really matter, as it’s more of a mechanic of spells that can affect them, since the game is mechanic-driven.
Gnolls are racist? How? That claim was quite poorly explained and was just dropped there for what reason? That is the most asinine comment I have heard in a while. They are a cursed race and are going to act as such. If you’re that concerned over how they are portrayed, then change it in your own campaign. Change the social structure, how they act, make them cured of their curse and they are working on redeeming themselves. Take inspiration from Warcraft and the Orcs corrupted by a demon’s blood, where they were bloodthirsty. The gnolls are basically the same way. Before the orcs were corrupted by the demon’s blood, they were nomadic with a strong warrior culture that valued honor. Recently in warcraft lore, the orcs freed themselves from the corruption of the demon’s blood and they are returning to their former ways. You can have the gnolls follow a similar path and work on establishing themselves as a respectable race.
The gnoll lore has been a part of D&D history since their inception, and unless their curse has been cured, it’s not going to change. Also, they are a fictional race, so their portrayal can be however you want them to be, but you’re getting yourself worked up over something that is non-existent, and, honestly, quite a trivial matter. If you don’t like it, change it in your games. Problem solved. But the criticism of the how they are portrayed in 5e doesn’t stand on much, and, again, is quite pointless because they are a fictional race.
Finally, the criticism of D&D and matriarchal societies. They portray the evils of sexism. While there are plenty of portrayals of sexism against women, there are little portrayals of sexism against men. The drow do that. Additionally, they are evil because they are a theocratic society that literally worships an evil god. I’m pretty sure worshipping an evil god will make you evil. Obviously, there are exceptions to the rule in D&D lore, and PCs can be the exceptions the the rule. But what’s great about D&D is that you can change what you do not like about certain races in your own campaigns and alter them to how you see fit, and 5e enables you to do that. So if you want to see gnolls and drow be different, make them different in your own setting or make a PC who is different and have one of their motivations to change things in their setting. Things don’t have to follow the book.