Well, Donald's still in it far more than the original series and he does get several episodes focusing on him.
And how exactly does smart nerd equal Dipper clone? Smart nerd characters have existed for decades long before Dipper Pines was created. Velma Dinkley's a smart nerd too, are you gonna call all the smart nerd characters a clone of Velma?
I don't see how Dewey's that much a jerk. He's more of an impulsive adventure loving guy with a slight showmanship attitude but not a jerk. And he does get character development later on.
Louie also does go through character development later on to use his seeing all the angles talent for good and helping others like in The Trickening, Rumble for Ragnorak, and Louie's Eleven. And character flaws shouldn't be bad inherently since it gives good character development. Besides, there are a lot of great greedy guys with hearts of gold that exist like Daffy Duck on The Looney Tunes Show, Eddy from Ed Edd n Eddy, Kuzco on Emperor's New Groove, and Timmy Turner on the Fairly OddParents.
And compared to how ruthless and nasty they were in the original shorts where they antagonize Donald, Dewey and Louie are far more likable and nicer here.
Do you really believe that Matt and Frank decided to run the show just so they could turn a show they loved watching when they were kids into Gravity Ducks? Matt Youngberg and Frank Angones didn't even work on Gravity Falls to begin with.
Besides, just because it has overarching story arcs and mysteries doesn't make it a Gravity Falls clone. Like Avatar, Steven Universe, Star vs the Forces of Evil, Rapunzel's Tangled Adventure, OK KO, Amphibia, Owl House, Big Hero 6 The Series, Teenage Mutant Ninja Turtles 2012, Scooby Doo Mystery Incorporated, Adventure Time, Legend of Korra, the Ben 10 franchise, She Ra 2018, Carmen Sandiego 2019, and Young Justice are like that, are they Gravity Falls clones too?
Heck, Webby isn't that much like Mabel. I know in the past you've said they're "loud, excitable, and crazy" but that's hardly enough to make them that similar since Webby's not into guys, she isn't as overly girly as Mabel (granted Webby's still feminine here, but not Mabel levels), is more into adventuring, less selfish, and more paranoid. Like what would it take to try and prove Webby isn't Mabel 2.0?
Besides, gotta admit, it does beat her 1987 self who was a pretty flat character that played the innocent girl schtick a bit too much. And even people who love or even prefer the 1987 show aren't exactly gonna consider 1987 Webby the best character there and don't think too highly of her there.
I'm not trying to call you a bad person for not liking the show, I'm just trying to bring up some points to you is all.