Why does a VPN connection change how Windows discovers devices on the local network?

When I connect to a VPN on my Windows PC, I can no longer see other computers or network devices like printers and media servers that are normally visible on my local home network. I suspect the VPN is rerouting my network traffic and changing how Windows handles network discovery and name resolution, but I need to understand exactly why this happens and whether there is a setting to allow local device discovery while still using the VPN connection.