I was so close, too!
imo it was when i stopped playing peach, now I do what i think works and it's more correct
I got more perspective on her tools and what they're good for, and thought a whole lot about why I lose.
truth be told i'm pretty much the archetypical scrub, the only wins I got for the first 2-3 years of me playing were 'cause I could dsmash like I really wanted it, and I "improved" because I played all the ****in time while *actually* maturing and getting smarter
but all I really did was turnip fair, dsmash, dash attack, and spam fc nair inneffectively LOL but I did it with a whole lot of willpower so it worked more often than it would on paper, which is why people hate losing to me
TBH I never read anything on the peach boards that really helped that much, because if someone told me "oh you gotta dtilt sheik" that was all I'd do because I read it as a solution to the problem instead of a tool. (only exception was when I read that beats midtiers, 'cause that works in real life)
falcon made me stop trying to cc dsmash foxes and wd out of the way instead, and actually think about where I was going when I move and whatnot. I'd jump in knee fullscreen and people would just completely outspace it, so it was like "oh if I attack whenever I want I'll get *****" which was a connection I never made with peach, and a whole lotta other **** like that involving rolling, jumping, grabbing, etc
it also helps that I think about this game all the time and actually try to put in the effort to becoming top level instead of saying that I do and then complaining when I lose to randoms
Edit: Y'all know how ben grimm got 5th at no johns? Doing exactly what I did, by dsmashing with willpower and wanting it really bad. I just hope he's able to obtain the same perspective and maturity I did.