That probably only sounds high to some people because they were strongly predicting $399. All things considered it seems like MS doesn't want to take a major financial hit on XOX (kiss hug kiss) in order to get higher sales.
Sensible in the longterm perspective. Profitability of the Xbox is more important than number of units sold and it's clear XOS will be an important unit for entry-level buyers for a few years yet. They possibly looked at PS4 vs PS4P sales and realised that the premium unit is not going to supersede the base unit in sales volume, so there is no point trying to take a volume approach to XOX at the cost of profitability.
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