“bottled spells”

"Bottled spells" that don't recharge on a long rest but instead cost an arm and a leg and heal for a pittance, basically ensuring that in the time that it takes to gulp one down you've already taken twice as much damage than what it'll heal. I guess I get the idea but RAW, the potions are just awful outside of last resort to bring up downed characters (and that's assuming your GM has no problems making an unconscious character forcibly drink them).

I'm surprised they didn't make the list given the general popularity, but let's be real here, Goblin Slayer is honestly mediocre and Shield Hero has been spiraling down the drain ever since it started.

While I do often feel that way too, it needs to be pointed out that Anime Corner is a bit of a niche site and this reflects only the opinions of 5408 people. Their polls are known to have a bit wack results at times. If you look at other sites, MAL for example has had 25k people rate the list's top entry, Sousou no Frieren. If you want to truly gauge something's popularity, it's worth looking at more than just one site.

No offense to any potential fans but I do have to say how depressing I find it that any even remotely original anime are never getting a second season yet a million cookie cutter faux medieval European fantasy harems are greenlit every day. I get that they produce whatever sells but surely people will have to grow bored of the same thing being done over and over again? Surely...?

Okay, explain to me why do you need rules for holding your breath in 5e.

Because water is generally everywhere and you might go in it? Surviving poisonous gases? Strangulation? If you wanted to point at rarely used rules there's a plethora of better options to pick. This is more like asking why do you need rules for combat.

Why are people just accepting casters taking forever to pick their spells? They should preplan their turns during other creatures turns. If your wizard is spending 15 minutes to pick a spell, it's your DM's duty to tell them that they're skipping their turn as the character is too indecisive to figure out what to do, better plan for your next turn instead. If a player is consistently slowing down the game multiple orders of magnitude they either need to learn what their character can do and make snappier decisions or play a class with less choices. There is no reason to tolerate people wasting other players' time to the point it's making the game unenjoyable for them.

The "adventuring day" is a relic of times when your entire campaign was exploring a megadungeon and you ran from one encounter to another, back to back, all night long. But barely anybody runs their game like that these days and the rules just never caught up with reality. Some people suggest having a constant time pressure on the party limiting long rests, and while it can work, it also puts a straitjacket on your story pacing where balance flies out the window if you ever let up on the pressure. "Guys, the apocalypse is merely hours away" quickly gets old when it's been that way for months.

Well, that and 99% of the rules involve fighting or exploring. Anything the rulebooks have to say on social interaction boils down to "well, you just talk to the DM, and sometimes they might have you roll a d20, just figure something out". D&D isn't really so much a role-playing game as it is a weird dungeon-crawling boardgame with some role-play elements. Sadly, people are allergic to trying new systems so instead they'll just try to bodge the one big-name king of TTRPGs, D&D, into doing things it was never built for, forever leaving them wondering why driving in screws with a hammer isn't as fun as they expected.

If you have a mean DM, get a new DM. D&D isn't an adversarial game where a DM plays to win or turn every player plan on their head like an evil genie. Even if they get to decide what kind of creature the players get, they should pick whatever would be the most fun to introduce to the scene, not whatever would be the worst for the players. If they can come up with something that isn't the most obvious good pick and surprises the players while being useful in their own way, it's a good pick. Not to mention, usually forcing the players to improvise parts of their strategy on the fly leads to more fun play than just letting them steamroll an encounter using a predetermined, infallible plan.

The more I look into it the more I start to feel like it's entirely intentional. As OP mentions, the other forms of polymorph explicitly spell out you get to choose, but normal polymorph does not.

Also, while it's of course not directly related to DnD, there are some older dungeon crawling media that have both been inspired by DnD and been an inspiration to it that run with this interpretation. For example, in Nethack, a dungeon crawling game first released in 1987, polymorph is entirely random making it a gamble. At least DnD 5e caps the challenge rating so at worst you'd get another monster in the same ballpark strength as you had initially, in Nethack you could just as easily turn a goblin into a dragon.

Castlevania > Demon Slayer (Kimetsu No Yaiba)

The only mildly warm part of this take is that Castlevania isn't really anime but western animation.

Demon Slayer has amazing visuals thanks to Ufotable, but outside of that the story and characters are as bland as, if not even worse than in any other painfully mediocre battle shonen to ever come out. If you look at shows as a whole instead of hyper-focusing on animation quality, pretty much anything with even mediocre writing will beat it.

Perhaps because people aren't going around calling others "males" to demean them?

These are not difficult concepts if you turn on your brain.

Which is exactly why you shouldn't be using them in a situation that clearly calls for a switch.