I don't think they have to wait until their sales slow down. Consumers appreciate a vendor that respects their intelligence. Nothing is preventing Sony from reflecting the factual value difference in the price BEFORE being arm twisted by the market. Or to increase the value of their offer to make up for the competition's moves: lower game prices, Answers to Xcloud and AllAccess, better accessiblity to 1st party games, etc.. Both approaches would benefit consumers and I am taking the consumer's perspective here. Not the "Does it maximise the corporation's profits" perspective. It's not my job to worry about that.
Console manufacturers have always analysed the triangle of price, value proposition and sales to proactively steer future demand. I refer to this article from 2008 about the price competition between the PS3 and the Xbox 360:
Sony, on the other hand, is eliminating its 40GB $399 PS 3 model entirely. The 80GB version which was $499 will now cost $399. Microsoft now has the most expensive box on the market, with the Xbox 360 Elite with a 120GB hard drive now costing $449. Microsoft will likely have to cut prices in reaction or lose market share. https://venturebeat.com/2008/07/15/...the-sony-playstation-3-joins-the-console-war/
You don't have to lose market share to adjust your price. In many cases it's already too late then. A smart company sells you a product for what it's worth today instead of banking on you ignoring the real value. The value changed with the Bethesda acquisition combined with all the moves that Xbox has made in the last 2 years. I'm just saying that Sony can no longer afford to just ignore it. The article above made the same point about a different situation 12 years ago.
I think you are letting your own hype get the better of you, because it's not like this is going to change much.
Before this acquisition, MS's first party studios were paltry and almost nonexistent compared to the big first party lineup from Sony that basically guarantees hit after hit after hit.
Now after the acquisition, MS is almost basically tied with Sony, while Sony is still offering the same top class studios plus you get first class treatment with most third party studios.
You want the earliest access in COD? You got it. You want to play Final Fantasy the earliest? You got it. You want to play a remake of Silent Hill console exclusive? You got it.
I just don't see how anything has changed that significantly. It's not like Bethesda's games have performed well recently, all their recent games including Doom Eternal have significantly underperformed in the market, which is why they were open to an acquisition in the first place.
The only significant games in the market place is ES and maybe Star Field, and Bethesda isn't releasing them the next year, perhaps not even during the next two years. How are they going to affect anything by that point?
Your entire premise is fueled by fanboy excitement rather than any objectivity. That's why it can be summed up as a more complex way of going "jeez guys, MS is totally destroying Sony, they am doomed!!!".