This has nothing to do with 3D. The formats that were listed are proprietary lossy-compressed RAW digital cinema (video) file formats (except BRAW which is technically not a true RAW format, but likes to pretend to be one by providing a useful subset of its advantages). Some of the cameras which use these formats can capture pseudo-stills in these formats by recording them essentially as single-frame clips.
While the formats are proprietary, at least R3D (RED Digital Cinema) and BRAW (Blackmagic Design) have SDKs available for 3rd parties to support reading the formats in other software. Not sure about Arri RAW, and personally don't really care.
While it would be perfectly reasonable for Serif to support using the available SDKs to open single-frame clips from these cameras, the notion that photo software is somehow less "professional" because it doesn't support reading these highly specialized digital cinema formats is so preposterous it is laughable.
I think not so many people use 3D, so why should Serif this develop.
And as photographer can ask yourself Do I need 3D, then choose the software that can do that.
But thats my opinion.
