Hardly any Germans live there. Yes they were expelled, but this is Russian land now. It would be a violation of their self-determination to give them to a country they are so different from.
True, but f**k that. We are talking about Russia here. If Ukraine is supposedly a threat to Russia then Kaliningrad most certainly is a threat to its western neighbours. The west continously brings knives to gunfights. Russia threatening to take Crimea and Donbass back in 2014 could probably have been refuted with western threats of taking Kaliningrad in response.