If it wasn't at a speed disadvantage compared to a fighter of equal power and humanoid size, there'd be no reason to use a word that specifically translates to "slow, dull."
Paragus specifically said ugoki ga nibui Oozaru no henshin which translates to "the giant monkey transformation with dull movement," which is basically calling it slow and uncoordinated.
Also, Zarbon, whose transformation doesn't even double his power, said the Oozaru form just makes the Saiyan unnecessarily large. Sounds like it isn't a speed increaser to me, if it were then Zarbon and Dodoria would have no way whatsoever to defeat Saiyan arc Vegeta once he gets his fake moon...
Piccolo's power doesn't increase in the least in his giant form, he even said so himself. Oozaru multiplies Ki output by 10x, Goku never said he had gotten so much faster, and if he did, such an increase in size would just make him hit harder with his weight. I fail to see how it would be...
Piccolo is a worse fighter because he literally gets as big as a mountain and Goku can jump into his mouth. When he was only Oozaru sized his size wasn't a hindrance for him.
Zeno might be immune to the Super DBs given that he overrode Zamasu's immortality @最強のフュージョン
I also think they took delight in killing the mortals one by one rather than mass-erasing them all at once as Zen-o would be able to. The plot of the Zamasu arc is asstrash but there's some reasoning...
Yeah I think AT just forgot that King Cold was unknown to Vegeta during the Z portion of the manga. Wouldn't be the first time he forgot shit in recent media, he also forgot Bardock's original outfit in the exact same sequence which he depicted in the manga, when he wrote the Broly movie.
Imo bulky transformations that still increase speed like Oozaru and Grade 2 have disproportionately low speed in comparison to their power. When you observe Vegeta's fight with Semi Cell you notice he relies much more on heavy-hitting single attacks rather than barrages of attacks that he...
AT had Paragus openly state that Broly's Ikari form allowed him to use Oozaru power in an agile human body as opposed to the slow, hulking Oozaru transformation.