This is just an example of lightweight desktop visualization application that I think are not viable in the long term anymore. It may fulfill the needs of its single developer and handful of users for a few projects, but for example if you want to see the images (not just extracted surfaces), or you need to segment additional structures, or visualize surgical tools, or import DICOM data, or export plans, or interface with guidance systems, etc. then you realize that there is a lot of implementation and integration work to do. Such small tools/libraries can serve as a feasibility prototype for a full application or it can be used as a library in an application (for example, if you like the visualization modes that it offers then you could pip install and use it in 3D Slicer to use it with combination of existing surgical planning tools).
If you want to find the best possible solution (robust, accurate, and fast enough) then you need to implement all the promising options and test it with your typical data sets, on typical hardware configurations.
If you find that none of the methods are fast enough to operate on the full-resolution data then you can use level-of-detail technique to achieve arbitrarily fast clipping, at the cost of temporary image degradation (use a lower-resolution mesh while interacting with the clipping plane and compute the full-resolution result when the plane is not moving anymore).