Imagine, you're a kid in the early 2010s, you still don't know what anime is, even if you watched some of them, you like fighting movies, medieval movies with magic, you like some goofy cartoons, but you love action packed content.
You watch on youtube an short part of Kakashi x Zabuza, you see two characters having short fights then stopping to do some strange movement with their hands, then something magic appears on the flor, and instead of watching an exiting fight, you watch two dudes stop several times to make movements and weird things happened, then you forget thisnshit you saw and think Naruto is only this until you became a teen at the late 2010s
Yeah, it was my first experience with Naruto, and if wasn't for the handseals, i would got into naruto when i was like 10 or 11.
Let's be serious, when you watch some anime or movie that has fighting, you want see two people battling with fist, weapons, or Any type of Magic, it is fast and fluid.
All the short videos i watched where fights had more handseals, it was Anticlimatic af, and most of the Jutsus that used Handseals wasn't fluid, like two characters very far from each other, both of them still, one of them make a long ass handseal, and a rolling rock appear in the floor and attacks the opponent, the opponent dodges thw attack, then stay still while doing another long ass handseal and appears hole spitting fire in the character.
Like this is totally anticlimatic, and most fights that feature handseals are like the example i gave: Boring, anticlimatic, and looks nothing like a fight. Just two dudes doing some goofy hand movements while totaly still.