Does this mean that the display automatically defaults to widescreen?
The default capture setting for performers is now widescreen, yes. Performers who have elected to change their settings from the default values haven't had any settings changed.
I have seen some performers in widescreen, and something is wrong. As with widescreen televisions trying to display programs not filmed that way, some of the performers now appear stretched out and wider than they actually are. They now appear significantly different from their profile pics.
The problem you're mentioning is at the capture side, not at the display side. Many performers choose to use cam-splitting software for various reasons and often times that software doesn't behave the way it ought to. The misbehavior manifests itself in many ways, the two most noticeable ways being the 'stretching' effect or 'black bars' on either side of the video.
Performers who choose to use the cam-splitting software are responsible for making sure its working the way it should be.
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