I feel these sockets may have been a practical choice for power supplies that extend too far up or down. This approach gives the best of both worlds for them to be able to plug in whatever is needed. Why are they in the ceiling above a dart board? No clue…

Sort of? https://developers.cloudflare.com/cloudflare-one/connections/connect-apps/use-cases/rdp/ - I have no idea how to do it though.

I’ve had SSH and VNC sessions rendered in web pages with tunnels, but never RDP.

I would prefer to use TailScale (www.tailscale.com) for something like RDP though, much easier to configure / set up and again you’re hiding behind their infrastructure.

Cloudflare tunnels is the way to go for small self hosted content. You’re hiding behind their ddos protection and your IP / location remains hidden from end users.