Sea tactics are called line tactics, which were actually invented by the British. It is stipulated that everyone should line up, walk together and fire together, with the purpose of facilitating supervision (everyone is in the same line, and whoever slacks can be seen by the commander at once), so it is written into the naval warfare regulations and regarded as a dogma.

Of course, there are also irregularities. Nelson, for example, adopted the melee mode in Trafalgar.

Later, with the popularization of radio technology, naval tactics became flexible, but in order to exert firepower, more line tactics were adopted. After all, the sea is large enough and relatively flat.

But the land is different, the terrain is undulating, and everyone's speed of progress is bound to be different. If they attack in a line, the formation will soon be chaotic (as evidenced by the defeat of the Macedonian phalanx by the Romans in the past)