I think it's a good thread in signal to noise ratio.  The bulk of the verbiage has been productive and spot on.  

So going back as far as 1e, per Sposta, Gnolls have been an arguably playable race.  It does seem that Gnolls in 5e are the stand in for the "essential evil" folk, they presently wear this editions universal "kick me" sign.  Anyone ever watch the animation before the D&D Beyond Dev updates?  "Why gnolls?" was my first response in seeing that; but I do see having read more extensively that in this edition they have been compartmentalized into the dehumanized zone.  That doesn't mean it needs to stay that way.  Seems every other edition makes an effort to un-demonize and un-monsterfy other humanoids, and Gnolls are a quick fix, easy port from the Monster Manual to a homebrew race.  

Honestly, it may break from FR as described, but my game's FR and the world it's ramping into, Goblinoids, etc. are part of the comsmopolitan vibe in many places (the Elves and the Dwarves are the only ones who really maintain ethno-states ... well there is a Hobgoblin nation, but they're very colonial and other races can serve in their ranks too, just not part of the ruling caste).  It's not a utopia, I'd say roughly a third of the active world is largely "classic good guys" races with some goblinoid etc presence, another third is "classic badlands" largely goblinoid etc governed but a fair presence of the "classic good guys" and a third is pretty much a mix (guess which demographic environment holds the most opportunity?).  If you look at a map it's very clear there was a war, and you can tell where the historical "sides" were but all that really happened in the end was population shifts.  There's even greater fluidity cohabitation in the Feywild and Shadowfell.  I don't really think much as to whether this is how I "should" be playing D&D; but I can say it works for my groups.

Doubtless it's already been mentioned.  But there's a perfectly valid PC stat block for a playable gnoll (playable gnoll, playable gnoll!) in Keith Baker's Exploring Eberron, an absolutely top-notch and utterly fantastic DM's Guild product.  Keith Baker wrote Eberron in the first place, he was deeply involved in the 5e rebake of Eberron, and Exploring Eberron is only "unofficial" because Wizards didn't want to print two books on Eberron in one year.

For obvious reasons I can't reprint the entire stat block here, but it's not really difficult to recreate it on DDB as homebrew.  I've done so myself.  There's some fiddling required to get it to come out just right, as Keith and his team included some choice points in the Znir Pact gnoll that don't exist in normal PC species, but for a specific PC you can ignore those choice points and simply build a character-specific entry with the player's choices already hard-coded in.  That makes it no issue at all to brew up for a player, and frankly I could see Wizards including the Znir Pact stat block in their next edition of Volo's Guide to DM Headaches.  It's pretty well in line with any other Eberron species; it's pretty heavily loaded by base PHB standards, but that goes for literally every species in the Eberron book including the Dragonmark reprints of base PHB species, so it's just kinda how they be.

EDIT: @Midnight
The D&D Beyond jingle was referencing a specific scene in Critical Role, where the player group was delving into a mine serving as a home base for a gnoll raider band.  Sam Riegel (who invented the jingle) referenced the events of the game in said jingle, and the DDB team had parts of that episode as the basis for their animation.  It's not a DDB-fabricated dig on gnolls, it's simply a byproduct of where the song came from.

The Keith Baker gnoll is similar to the Custom Lineage gnoll, here in this thread, that reflavors the Tavern Brawler feat as Feral Ferocity.

Medium humanoid with Darkvision, +2 Strength and +1 Constitution.

Like the Tavern Brawler, the gnoll bite is a normal unarmed attack dealing 1d4 damage, except the Baker gnoll unarmed attack deals piercing damage instead of bludgeoning damage. This override for piercing damage seems unnecessary, because in the case of a reallife hyena, the molars and short teeth are more for crushing bones than stabbing. The standard bludgeoning damage is appropriate for a hyena bite. The hyena has one of the strongest bites of any animal on the planet, again for crushing and eating bones. Bludgeoning damage.

The Baker gnoll includes the Monster Manual gnoll trait, "Rampage", that grants a bonus action attack if reducing an opponent to zero hit points. But this trait is modest in potency, and not especially hyena-like.

Finally, the Baker gnoll mentions the option of swapping Dexterity for Strength. Hyenas dont seem especially dexterous. Since the gnolls are big (7 to 8 feet tall) with crushing bites, the Strength makes more sense thematically. Meanwhile, Tashas lets any player swap any ability score improvement, anyway, if someone wanted a dexterity concept.

The Baker gnoll allows a choice between certain skills, but the Monster Manual gnoll lacks an extra skill.

In sum, some many gnoll players may prefer the Custom Lineage version of the gnoll.

The Znir Pact gnoll offers a skill proficiency, darkvision, the bite, a modified Rampage trait, and basic PC stuff.  It comes with a +2/+1 stat spread and no bonus feat.

The Custom Lineage "gnoll" gets darkvision OR a skill proficiency, not both.  It drops Rampage in exchange for Tavern Brawler improvised weapon nonsense nobody uses, and both gain a 1d4 unarmed strike.  The CL gnoll can grapple as a bonus action if it punches/bites and gains a +3 to Strength counting the feat's boost.

I'm admittedly deeply prone to an extremely low opinion of the Custom Lineage system, but in this case I suppose the CL "gnoll" is loosely comparable.  Definitely not equivalent, given the lost skill and the fact that Tavern Brawler's improvised weapon shenanery is not nearly as powerful as the Znir Pact gnoll's Rampage, but it's doable enough for someone trying to be cheeky in AL, I suppose.