You're looking at things in a bubble. A price cut isn't going to be announced for only one region, it's a global strategy. A lot of factors have to be considered.
Right now, the PS4 is dominating EMEA. In the US, it's more competitive, but the PS4 is still leading. Even after December, that will still be the case. At which point, we enter the smaller months, and even if Xbox One continues to outsell it (which I don't believe will happen consistently), that lead would mostly remain or they'd mostly be on equal footing until the next big Holiday quarter. This is ignoring the revenue which would suffer a big impact from cutting the price in such a short-sighted move. I'll keep this very simple here since it's more complicated really. But let's say I cut $50 off the price of the system, but have effectively reduced my profit margin from $70 to $20. How many more sales am I really going to push over the Holiday season, and what does it mean for my bottom line? Neglecting that, what's the forecasting looking like for the console at its current pricing? And what does cutting the price now mean long-term because I can't simply cut price every year? After doing all these calculations, what about the other regions? What does it mean for them? SCEE where everything is fantastic, or SCEJ/A where they're still waiting on getting some momentum going and a price cut would be better strategically placed next to a huge title to help push it. All of this has to be taken into consideration.
Xbox One is doing well after dropping the price $170 in a year, but their desperation was necessary. They cut their own legs off by starting at $499, and they know that they cannot afford to be anything less than competitive in the US. That is simply far too important for them. Even so, they're closing in on 10 million units shipped now as per their last release. PS4 has remained at $399 from the beginning and is closing in on 20 million units shipped.
No company makes such a short sighted move based off one month's results, especially when it's affecting one region and to a mostly insignificant extent. I'm sure SCEA executives will sit down and plan thoroughly for whatever they want to do, but it's not just about cutting price. Maximising the potential of the PS4 at its current pricing is part of the longevity of the system. Lots of people continue to purchase the system, and it's setting a fantastic pace for sales. We're now leaving the biggest quarter of the year so cutting price at this stage would be idiotic. Cutting price prior to entering it would be equally idiotic considering the strength of sales, and the fact that we're entering the biggest quarter of the year.
A price cut isn't necessary. SCEA has done fine this month. Where they messed up is with their marketing and promotional push in face of a much more aggressive Microsoft, but to be fair, there was only so much that could be countered there.