Don't humans have the ability to fuck everything? It's why half elves and half orcs exist, but no non-human hybrids.

Humans get to slowly raise the temperature of the world over 100 years until it causes a mass extinction event. It's very effective.

Vumans get a feat, which is arguably one of the strongest abilities. Base humans are notoriously weak though.

Don't humans get two extra proficiencies to represent their adaptability and quick learning?

There is legitimately an issue in all fantasy games where designers build a rich diverse setting with many different races that have their own exciting cultures and designs and differences, but if they include "human" about 50% of players choose human. This persists through boardgames, RPGs, videogames and LARP. The exact proportions vary a bit from game to game and from playerbase to playerbase, but it's very common.

Larian revealed some stats a while back for BG3, about 50% of players chose human, elf, or half-elf (the three most "human" looking races". If you choose one of the existing characters to play as, Gale is the most common. It's an encouraging result, there's more diversity in the picks for BG3 than most other games, but it's still very "human" skewed. Halfling, Gnome and Gith were much less commonly picked.

If you've been tabletop gaming for a long time, your instinct is to think things like "but why would anyone play as a human? that's boring!" or "I play these games for escapism and I want to play as something different to myself." or the like, but the reality is that there's a very large cadre of players who want to create characters or avatars that are "like them" - they want to self-insert, or they want to pretend they are their character, and have difficulty squaring that with being a gnome or a goblin or a Dragonborn.

As such, you can get this weird disconnect between your setting writing (where there's a large variety of different, interesting races in the world) and your playerbase (majority human) which skews your design towards a human-centric viewpoint that you don't necessarily want - especially if you put work into the design of cultures of other races, and you want players to explore a variety of ideas and styles.

So what's the solution? - a common design solution is to mechanically incentivise players to choose outside of human, by giving humans disadvantages, or giving other races unique advantages that are desirable. Is this the right approach? your mileage might vary, but it's one of the easiest "patches" to encourage diversity in the playerbase, so it's a common choice.

Does 5e do this? probably not - human is very mechanically powerful, especially at low levels where the variant human feat can make a big difference... but they did make humans more "boring" than the other races, hopefully encouraging more dragonborn and gnomes and half-orcs and so on.

Humans get privilege.

Humans should get "All healing received is maximized (ie: treat it as if the dice each rolled their maximum value)" to reflect how humans weirdly bounce back from things that should have been fatal.

Most races get more darkvision

Half-lings get more luck

Dragonborn get more breath weapons

Humans get more

They have the power of discrimination on their side

Humans in OneDnD have an insp point they can toss on shit now which is pretty cool, feels like an embracing of the trope that humans will act as a glue that can bridge cultural differences between other races.

I play mostly d&d 3.5 and pathfinder 1e And I think human is the most powerful race with his free feat level one ^^

Humans get to know that they're better than everyone like how batman is better than superman

Humans get to..(checks literary notes) not be genocided by other humans, until the xeno menace is destroyed.

Variant Humans get to choose their own ability.

Humans max out their primary at level 4, most op racial ever