Power was one of many narratives at the start of last gen. Alone with drm and price and Kinect. And I understand as during launch there where barely any new games. So yea it changed mid way when Sony started pushing out great games and MS basicly stop. And it also happened during 7th I guess, I was not here for that. But I'm gona go on a limb and say it also stoped when it was clear that Sony was not gona pull ahead but their games Sure did.
For some odd reason GAMES tend to be the focus of GAMING CONSOLES and every other topic falls to the side eventually.
Edit: reminds me of the x1s 4k br player. It was gona change the market because that was a feture that put ps2 and ps3 ahead. Obiously not the games.
Power never determines a consoles success, however it doesn't mean it was never the narrative, the internet blows up, the fanboys start fighting while the average consumer really doesn't care, normally its the price that makes a bigger difference for them. If we want to be calling Xbox out for being power driven, than Sony has to be called out too. They pushed power with almost all their generations dating back to the PS2 vs Dreamcast with their Emotion Engine etc. Much like Xbox and Nintendo when they have/had the advantages.
You seem to confuse fan bickering with company marketing and media coverage.
Sony didn't said PS4 was the strongest for several months before launch. They said how many Tflops it had, that it was easy to develop (acknowledging PS3 wasn't) and that they worked to make it very balanced (removing as many bottlenecks as they could), fans run with it. MS gone in defense mode and had Albert Penello saying:
"I’m not dismissing raw performance. I’m stating – as I have stated from the beginning – that the performance delta between the two platforms is not as great as the raw numbers lead the average consumer to believe," Penello wrote on NeoGAF. "There are things about our system architecture not fully understood, and there are things about theirs as well, that bring the two systems into balance."
"People DO understand that Microsoft has some of the smartest graphics programmers IN THE WORLD. We CREATED DirectX, the standard API’s that everyone programs against. So while people laude Sony for their [hardware] skills, do you really think we don’t know how to build a system optimized for maximizing graphics for programmers? Seriously? There is no way we’re giving up a 30%+ advantage to Sony. And ANYONE who has seen both systems running could say there are great looking games on both systems. If there was really huge performance difference – it would be obvious."
So if don't try to rewrite the story you'll see that the company that have been talking about power and how the competitor compared was MS with they not being behind in X1, with X1X being the most powerful ever, and now with XSX it is the most powerful ever again then got changed to most powerful xbox ever. Sony didn't gave a fuck to Xbox or mentioning them, fans did.
And to compliment on launch the games were considerably performing better on PS4 instead of X1 so no one needed to find excuses (although we got articles saying the resolution difference didn't matter and that fps was the deal). This time the problem is that while everyone was expecting Xbox to outperform PS5 considerably (with the likes of Tom from Verge and Colt Eastwood thinking it could even reach 40-50% advantage and Albert Penello - yes again - saying that even Series S would end up outperforming PS5 because PS5 wouldn't be able to keep framerate) the games told a different story so we got excuses and complains.
On your point about power not being much relevant, yes most of us agree, but on your price deciding the outcome so will Series S outsell PS5?