Initially, [Darling in the] FranXX came on my radar because everyone latched on the supposed sexual innuendo (even Evirus). Later, Faust came strongly in favor, although on Smug.Loli instead of his own blog:

Do you like Trigger's Darling in the FranXX? Their early work was a little too cartoonish for my tastes, but when Darling in the FranXX came out in 2018, I think they really came into their own, commercially and artistically. The whole show has a clear, straight plot, and a new sheen of consummate professionalism that really gives the episodes a big boost. They've been compared to Gainax, but I think Trigger has a far more bitter, cynical sense of humor.

But what really pulled me over was the 4koma, which provided enough spoilers.

I think the largest feature of the early FranXX is its eclecticity, to the extent that it's difficult to identify any new element at all. Now, I was long on the record being okay with anime re-hashing and hopefully refining its tropes. But usually there's something... a key element. Not here. FranXX deliberately goes all out to make disturbing and fun show without bothering with a token inventiveness. And it may be better off by focusing on implementation.

Now, the setup itself is not all that amazing. I mean, sure, children soldiers. We saw that before, just off the top of my head in Stellvia, Shingu, Shingeki no Kyoujin, YuYuYu. Stellvia combined it with the lovebird crew. The level of the disturbing is about SukaSuka (which also featured wasteland with islands and the absurd monsters). But details were great. One thing that struck me in the opener episode was how the mecha and architeture design were used to impart a sense of large scale.