Look at Melee, down throw perfect pivot f-smash as Marth is a 1 frame link and PPU did it to Hungrybox at Apex
The Melee scene has been around for over 14 years. The best players absolutely HAVE TO employ highly technical moves to overcome their competition, and they have over 13 years of meta development to play with. If Smash 4 was 13 years old, I think we would be seeing the kind of unusual tech in Smash 4 that still isn't being commonly used. For example, difficult infinites are not required to win yet, so people aren't doing them, but if that became the only way to win? High level players would start doing them or they'd be replaced by new players who would. This is how things like Ice Climber's infinite in Melee came to be used. You don't think people were wobbling in the first 8 months after Melee came out do you? (sidenote: the term "wobbling" was apparently coined in 2006, almost 5 years after the release of Melee)
I don't even think its harder to do than wavedashing.
If you mess up the timing on a wavedash, you might get a sloppy wavedash that just doesn't travel as far or that spends a split second in the air before the airdodge part hits the ground. However, if you mess up a perfect pivot, you'll get a dash dance movement or a slow pivot. A sloppy wavedash can still work out for you, but if you were supposed to perfect pivot and dashdance instead, you're probably open to getting punished. I guess what I'm saying is that a bad wavedash can still be a wavedash that works, but a bad perfect pivot isn't even a perfect pivot anymore. It's kind of like comparing apples and oranges, but I would still say that wavedashing has a looser window because of how the move behaves when you get it "wrong".
And a big part of the difficulty in it isn't just the technical skill to do the perfect pivot, it's the practical application of it. Perfect pivots aren't near as useful as wavedashes, so it's more difficult to find places where it's actually a good idea to use them. I played against a Sheik yesterday, first time I've ever played against someone who used a LOT of perfect pivots... and they had no idea when to use them. I was clearly the superior fighter, but this person definitely had a lot more tech skill than me for those. They just didn't know when to actually use them.