No, that's an opinion.
Nami had shown smarts and her Zeus attack even injured Big Mom before. There's no reason she couldn't beat Ulti. She even said a big lightning attack would win before BM put a hole in Ulti.
Oda planned something but completely threw it out because he thinks Big Meme unpredictability is fun. He ruined the development of 4 characters. That's just bad writing, bad chapter.
No its not an opinion, no reason nami couldnt beat ULTI??? Are you joking???
Ulti was shown making luffy need gear 4 against her, received an thunder bagua from Yamato in her head, and a atack of 3 homies of a yonko. ALL OF THAT and still got up. Stop the cap.
Nami didint had a chance using only Zeus against a Full Ulti.
A YONKO USED 3 HOMIES AND WASNT ENOUGH. How nami with only Zeus would do shit??
And no, its not an opinion, its a fact. Nami Win against ulti here makes way more sense than Alabasta and ennies lobby fights, where she won against profissional Killers ALONE and after having her weapon just made and knowing nothing about it, and techiniques out of nowhere in ennies lobby.
Here , nami victory, makes an universe more of sense , you liking It or not!