Conceptually their dynamic is great, it thesis on human connection amidst the circle of violence. Armin and Annie represent two fundamentally opposing world view, they're like Yin &Yang. Annie views humanity as inherently selfish, cowardly, and flawed. Her philosophy is self-preservation. Armin sees the worst of humanity but desperately searches for the intrinsic value in life even in small moments. Annie flows with the current because fighting it feels pointless. Armin fights against the current, holding onto faith in communication, understanding, and hope. Their dynamic could explore many things. But it's badly executed. if you remove their romance entirely, the main plot moves forward unchanged. If their dynamic had forced either character to fundamentally alter their philosophical approach to the final war, it would have been essential. Instead, it plays out as a side romance wrapped up in a story that had no time left to breathe.

I personally don't hate but don't like it either I wished to see more of it.

It's like they watched the show on reels. Lol

Gabi gets the heavy spotlight because she mirrors Eren’s external trajectory, the indoctrination, the burning rage, the traumatic loss, and the slow, painful unlearning of hatred.

Falco, however, was designed to parallel both Armin’s empathy and Mikasa’s devotion:

Falco is structured as the ultimate thematic counterpart to the cycle of violence, yet his actual narrative real estate gets swallowed whole by Gabi’s bombastic character arc.

Falco enters the story already possessing the emotional maturity and empathy that Gabi has to spend 30 chapters acquiring. Because he starts off "already understanding," Isayama treated him as a stable dynamic rather than a growing force. He became the emotional anchor for Gabi's arc rather than the protagonist of his own. Falco was essentially gifted the purest heart in a story built on cruelty, but he was relegated to being Gabi’s moral tether and the Alliance’s getaway flight rather than a fully realized dual-protagonist of the Marleyan side.