Those who aren't mentally challenged would realize that Majestic Attire and Perfect Susanoo have the same literally everything because the former literally is the latter, but changed shape to fit onto Kurama. If you can't use PS, you can't use Majestic Attire. If you are mentally challenged you'd make stupid arguments like:
-The blade isn't the same so it's not PS despite everything else being the same, even though anyone who isn't a moron would come to the conclusion that at that moment in time before getting Hagoromo's power that's how the blade for Sasuke's PS looked. One would only come to a conclusion this stupid by believing that all PS have to be the same no matter what, which is based on nothing as no Susanoo have ever been exactly like in size, design, weaponry or power so why the actual hell would PS have to follow suit?
-Sasuke needed Jugo's help when Jugo wasn't feeding Sasuke power from the beginning. :lol He gave his Susanoo Senjutsu, not Sasuke himself.
-Sasuke needed Naruto's help even though Naruto didn't share any power with him directly either after he lost the initial cloak. Literally same issue as above.