A comparison: the giant Dogger Bank offshore wind farm project (multi-GW) cost somewhere in the $10bn range. On the other hand, Germany calculates with >$100bn for grid buildout within the next decade (https://www.netzentwicklungsplan.de/sites/default/files/2023...).
Also, having customers that rely on your grid but buy very little of your power is simply unappealing for operators, so I would assume that their pricing tries to disincentivise as much as possible (=> "they gonna overcharge you for the grid connection").