Starlink mini router, from a quick google search, has a 150ft range. Your coach is only 43ft, any wi-fi router should suffice for that length.
There are alternative options depending on your coach Wi-Fi setup. For example, I use a pepwave to broadcast Wi-Fi to my phone and all devices in the coach. You could consider the Starlink Wi-Fi like Campground Wi-Fi so you bring in the external source (WAN) to your pepwave, if you have one, and then that goes out of the pepwave like before. I actually use an Ethernet connection on mine so my Starlink connects to my Pepwave over Ethernet and I don't even use Starlink's wi-fi.
Short answer YES
Long answer posted, you have options to keep things even simpler if needed and change Internet sources without ever having to change Wi-Fi connections on streaming devices, TV's, computers, Alexa's, etc.