8K video recording capabilities are coming to Snapdragon 865-powered flagships this year, even though they will be mostly useless and potentially buggy, at least judging by a showcase video posted by Qualcomm on Youtube. It is important to note that the video was shot in November last year, so maybe Qualcomm managed to fix all these problems in the meantime, so maybe the upcoming Galaxy S20 phones will not be plagued with such issues.
https://www.notebookcheck.net/Qualcomm-showcases-8K-video-recorded-with-Snapdragon-865-powered-phone-quality-is-iffy.453017.0.html