This argument is frankly Irrelevant.I stopped taking the powerscaling seriously after Iris was revealed to be the Champion and her Dragonite lost to Dracovish - also Dracovish's first time battling btw lmao. The Iris battle should have been much later in the series or the battle takes place when Iris is only a Gym Leader and not yet a Champion. It just felt weird to go from beating up Gym Leaders and CotD's and suddenly fighting a champion out of nowhere, before even beating an Elite 4 member - felt way too rushed imo.
I find there's no point in trying to compare Pokemon strength. Ash will be scaled up in power whenever the writers want him to beat more powerful trainers, simple as that. It's why Ash's Pikachu can tie with a Latios and couple episodes later, lose to a random Snivy, and then in Alola beat 2 Legendary pokemon in the same tournament. If Charizard, Infernape, etc are brought back, they will be able to get the same wins that the JN team can.
Yes, Pokemon have always been scaled to be as strong based on Plot convenience. This is not true only with Dracovish. It is just as true in case of Infernape, Charizard, Sceptile, Ash Greninja etc.
That doesn't change the fact that the writers scaled Ash's current Journey's team to beyond Regional Champion tier.
I think it's silly to keep using the argument that Plot dictates strength of Ash's Pokemon and whatever he brings now will be just as strong etc. Going by that point; every single battle result is also based on the Plot. Every single fight within the battle etc is all determined by Plot. So completely disregarding everything this way just seems silly.
The simple fact is Ash's current team was scaled to a level that far exceeds something we've ever seen before. This is an objective fact. Claiming things like Charizard , Infernape would be just as strong if they are brought back etc is just an opinion (Which does have a strong rationale). But they haven't been brought back..
And to add to that; there is one particular incident in the series that further re-inforces Ash's Journey's team being ahead.
This is based on the battle with Paul. Paul explicitly asked Ash to only use the Pokemon he would be taking to the Master Class Tournament. And this was in a setting where he was literally surrounded by All of Ash's Pokemon (Including those he probably even saw before when he went to visit Oak and learn from him). Considering the Master Class Tournament essentially represents a tournament of the strongest trainers in the world and Ash specifically used his Journey's team; I'm inclined to believe this further re-inforces his Journey's team being ahead.
Edit:
And going back to your Dracovish defeat Iris's Pokemon argument.
1) We don't know whether Dracovish was trained off-screen or not. Also, if you can believe Iris becoming a Regional Champion; someone arguably inferior to one of the Worst Iterations of Ash who was nowhere close to Regional Champion; you can also accept the fact that Ash trained Dracovish off screen.