In practice, video is done by using the HDMI output of the camera which will spit out continous 4k output without the 30 min limit, and without all the issues of needing to flush this to CFe/SD/XQD cards. You then caputre it on either a laptop or stand alone video capture device which will have functionally limitless storage. The sensor and processing engine is still running the whole time though, which means the camera needs to be specced to handle this (and they are). The only limitation is that you can't record to the internal storage, and as explained that doesn't matter.