well yes and no.
the VideoCapture class is basic but only in the lack of flexibility. OpenCV has a ton of backends for common and uncommon APIs. all of those are supported (ok, some were removed, some unmaintained/obsolete, some may not be built by default).
if the manufacturer doesn’t bother to give their device a standard interface like USB UVC, which is supported by all operating systems, that’s their fault and you’re stuck with their SDK, that is maybe supported by OpenCV already, or else you’d have to write some code to adapt.