@BD3D I’ve also built a node group for camera field-of-view clipping.
I’ve used multiple Transform nodes to transform the whole scene to prepare for clipping, which I’m guessing collapses to a single matrix applied to each point. From a performance perspective it works well - even for camera fly mode where recalculation is done for each frame.
You can download for free, and I’m happy for other people to build on this work.
Download link
YouTube node group details