On the computer display showing the various starships surroundings the space dock, the USS Clark is shown to be in two locations - top right and bottom left of the display.
Beverly says the Borg have not been seen or heard from on a decade. This is not true. In season 2, they went back in time where Agnes was taken over by the Borg Queen, and became the new Borg Queen herself. She stayed in the past and over the next 400 years built a Borg empire that did good instead of evil. The Borg should still be a known collective.
It would be extremely DUMB of Starfleet to now make their entire fleet of ships controllable from a single point. The threat of not one ship but all of them being taken over by any hostile force would be immeasurable (which is exactly what happens here).
Picard and Crusher speak of "neither transceivers nor receivers" but the transceiver was invented in the 1920s to mean, by definition, both TRANSmitter and reCEIVER. They should either have spoken of "no transceivers" or used "neither transmitters nor receivers".