[Q]

Some more observations regarding resupply of AI empires:

It is a game with me as human empire against 11 AI empires in team mod in a galaxy of about 150 systems at 2418.0.
The AI empires are huge compared with my empire with large number of ships: Sergetti have around 750 ships and they are not the biggest AI empire. They do have treaties with supplies sharing. They have researched solar collectors, but no ship design is using them (light cruiser is the current ship size with solar sails). As a consequence 3/4 of all ships are on low supplies, many of them have zero supplies which prevents almost all attacks on me.