I find it really weird that it's not until you get to the $200 range that anything has USB-C DP Alt mode support. You'd have though that anyone trying to squeeze space would want to drop full-size HDMI or DisplayPort ports at the first opportunity.

I will note that in theory there's the Radxa Cubie A7S, but that's unobtainium. Or I'd have bought three by now.

I switched from SBC to thin clients. You get the Dell wyse 5070 for 50 euros in my country and it has USB c dp alt mode and much more.