Well, if you can find a Pi anywhere! DAKboard is not open source, but there is a free version for home use, and it is pretty good apparently at what it does. Would be interesting to hear if there is a good fully open source alternative dedicated to displaying different types of data like this for a screen.
I suppose at a pinch, one could actually have a Pi just with a browser page on, displaying a dashboard that you have set up with Home Assistant. HA can also display photos, RSS feed, some house stats, etc too.
Personally, seeing I have just set up a nice Home Assistant dashboard, I'd probably start off with that and see how it goes. Now I have an excuse to buy a new monitor as all my older one's are way too small.
See I turned an old monitor into a digital dashboard — and it's a game changer
All the information I need each day, together in one place