We were looking for something like this too. One option that we found in the meantime:
Make a dashboard with just one report on it - the one you want to display. Since you only have one report, you can resize it on that dashboard to be fullscreen width. If you make your browser fullscreen (F11), and zoom your browser in you can make it so the report fills up the screen (not perfectly, but good enough).
We’ve also added extensions to our firefox browser to auto-refresh the browser window (this one works well enough: Tab Auto Refresh – Get this Extension for 🦊 Firefox (en-US)) and we also run a small “auto-tab” program on our PC connected to our display/monitor. Here is the program we use for that: https://www.softpedia.com/get/System/System-Miscellaneous/AutoTab.shtml.
This combination allows us to have multiple dashboards on several windows and we toggle through them with the auto-tab, and we refresh the dashboards with the auto-refresh tool (otherwise the dashboards don’t automatically update).
Hopefully this helps someone else!