Well the Block is for video normally HTML 5 has <video Controls > etc which allow to show controls. By default controls shows play, stop etc but also shows download
there is a tag controlsList="nodownload" which if placed after the controls disables the download button. However the block in the editor for the video reports this as invalid content is within the block.
even though it still functions. Typical other options which do work ok are like Autoplay.