I'll be very honest and try to do a good review (even if it's my first time) trying not to spoil the anime for those who are interested in watching. I call back, I would only say my personal opinion and I respect the choice and the tastes of others so please, don't hate me lmao.

So... What's the history ? I'm really lazy so I would put the story when we search Darling in The Franxx on French Wikipedia : In the distant and dystopian future, the surface of the Earth has become arid, inhospitable and dangerous to humans, continually targeted by wild beasts called “howlers”. By sheltering in gigantic air-conditioned mobile domes, called plantations, and by arming themselves with powerful combat robots, called "FranXX", they nevertheless manage to face the difficulties. The men are led by the Seven Sages and APE, an organization of scientists whose supreme leader is called “Papa”. Their army is made up of young soldiers, called Parasites, who are designed, educated, and selected solely for the purpose of fighting. With this in mind, they must synchronize by forming pistil-stamen pairs (girl-boy). They are kept in total ignorance of what is not related to their mission: to defend adults, until their last breath.
The history looks very interesting you might say, but I'm gonna say one thing and ALL the Dift fandom will insult me lmao, I keep it for the very end.

So basically the humans are living in a world where they have a very developed technology such as: being able to simulate the weather, being able to pilot giant robots, etc etc.... We are following the history of Shin- I mean Hiro and his squad, they will meet after a girl called Zero Two. Honestly, I really like the beginning of the anime (even though it reminds me of another anime...) but when we are in the fifteenth episode (approximately from memory), the anime ABSOLUTELY does not know where to go : they just keep doing like 2/3 secondary episodes that will only be used to develop certain characters and that's all, for example, they exploited all they have so what are we gonna do ? Copy another anim- I mean be more intelligent and try to create a new history !

I think that I will start to spoil a bit so.... You are warned ! SPOIL WARNING RIGHT NOW

So, the message hidden at the start of the anime, and which I personally found super interesting was that: Darling in the Franxx is indeed a critique of the absurdity of today's technological society which only has a short-term view, not concerned with the happiness of its elements and constantly seeking efficiency, even complexity. abusive. It is also a work proud of the qualities that make men: selflessness, determination, reason, compassion and passion. All these emotions are symbolized by the main couple, who brings them together and shares them with all those who wish to follow their example. We also see the impact of transhumanism, very present in the work, which is presented sometimes in a negative way, sometimes in a positive way according to its use and its creator (the Franxx, the autonomous cities, the framework of science fiction ...) . And honestly, that was really cool ! But of course, that's why I will now be insulted by all the Dift fandom : If Evangelion and Gurren Lagann would never have existed, Dift would never have existed. Let's be honest and I will maybe spoil Evangelion and Gurren Lagann so.... Sorry !

Let's talk first the similarities of Evangelion : Hiro. The protagonist is a pure copy of Shinji : they both are depressed, they reject others then they finally accept the others, they both are "special" to ride the robots, etc etc... Zero Two is a mixture between Rei (for her very mysterious side then revealed later in the anime) and Asuka (for her side of taking people from above and also being a bit like "depressed"). Then the universe : Evangelion is a mecha post-apocalyptic world, they both fight "Angels", they need only kids to ride the robots, they also have a "berserker mod", etc etc.... And Dift has also that.
Now the similarites of Gurren Lagann : like I said just before the anime does not know how to go after the fifteenth (approximately) so it starts to release super big "Angels" and the end is totally Gurren Lagann (I WILL SPOIL PART OF THE END OF GURREN LAGANN), Hiro and 02 merge to become even bigger and stronger, then they get beaten up a bit but with the power of love they get there and in the end ... I wouldn't say more. When I said they get a loot bigger it's really happening too in Gurren Lagann but Gurren Lagann is AT LEAST consistent with "why they get super strong".

And I think that's all so the good points: a loot of good ideas, sometimes good character develepoment.
Negative points: a copy of Evangelion and Gurren Lagann, a bad ending (I found), ideas very badly exploited and some characters that are almost useless
P.S : for the similarites for Evangelion, they are a LOT but I only just said the main ones.

Thanks for reading this review !