I think the $25,000/mo is just an opening gambit. For comparison, the list price for Starline Marine is $5,000/mo with a one-time hardware cost of $10,000, and even that seems padded to extract maximum value from yacht owners, cargo ships, etc.

Also, while I imagine the logistics of bouncing 350 MBps from satellite to satellite at 1000 km/h will impose significant overhead, a lot of the places where people will want this service the most (trans-Atlantic, trans-Pacific, Kansas cornfields etc) will have very few if any other users.