Very yes. They could reveal their location for starters, which could spoil a mission and put lives at risk, but if they use the same device on both this and the ships network, you risk compromising the ship’s network or even the Navy itself, giving our enemies all kinds of sensitive info.
We are in the midst of a world war being waged in cyberspace and the US is losing. Incidents like this are a genuine threat.
The world design is very gamey in Tsushima. A bunch of platforming jungle gyms with landscape filler in-between. Such a beautiful game, I would wish it looked more realistic. More Red Dead, less Far Cry.