We might as well attack the small ships. Destroying an Escort Ship reduces the opponent's barriers; taking down a cruiser lessens their firepower a bit.
This type of change is indeed effective.
The Mechanical Fleet began to incur losses.
Even if some small ships are destroyed, it still counts as a loss.
However, under the same conditions, the Alliance lost even more small ships.
Because the opponent is attacking in the same way.
Besides, the Alliance has other attempts: Interstellar Warriors.
Although there is no Spiritual Energy to assist in teleportation, it's impossible to quickly, smoothly, and reliably reach enemy ships. Nevertheless, Spiritual Transmission was never the only way for boarding operations.
Without Spiritual Energy, it doesn't mean boarding can't be done. In fact, a considerable number of battle groups, their Think Tanks do not have the ability to perform large-scale transportation, but how has everyone still managed to fight wars like this?