That’s a hard question to answer definitively. Boats aren’t like houses in that there are a lot more surfaces and materials that tend to mess with or block WiFi signals. It would depend on where the TVs are going to be located, and where the Starlink router is located.
Most boats around 60 feet or longer I have designed solutions for require two access points or WiFi routers for good coverage throughout the boat, especially further belowdecks.
Starlink does have a mesh product, which is essentially a second WiFi router that extends your range, but it is Starlink specific. I am not a big fan of using their equipment in general because of the lack of control and options. But it is an easy way to add more capacity.