Nobody over the age of 18, even at the time of GGG's TV run, was there for
Mamoru. He's important to the plot, he's done competently, but at best he's "Oh, hey" tier. He's the tagalong kid of the show, and you all know what kids in anime are for. They're for the
child demographic.
But hey, Shrimpdick wants to rape kids, so is this surprising?
And Brave - the metaseries GaoGaiGar belongs to - is literally the result of Takara saying "shit Transformers isn't popular anymore" and redistributing their efforts. There are
designs for toys that were literally wholesale lifted from
unused TF designs. Mix in super robot tropes and the guy (Okawara Kunio) who did the majority of the designs for Gundam. Well-a! You have Brave, brought to you by merchandising!
And Nagai's work
are the Super Robot. He is the creator of the goddaddy of them all, Mazinger. He influenced the creation of Getter Robot, which is just as influential. Sure, nobody cares about Jeeg or Violence Jack. But Shrimpy is simply delusional if he denies the influence of Nagai.