Security checks didn't really exist when Tegel opened in 1974. So the architect can at least be excused for not knowing about future requirements.

The worst for security that I've ever experienced was Amsterdam Schiphol. Absolute chaos at land side security and Americans on American airlines get extra inspection. When I was there they did the extra screening at the gate, but they've gone back and forth a bunch on where that's supposed to happen.

Tegel OTOH was super quick albeit poorly connected to the rest of Berlin.

At airports that do this I find it’s more common when US TSA adopts a rule first that people don’t want to subject all air passengers to. It was really common to have gate lines back when the US introduced that 3 oz bottle max.

The situation at AMS is that they kowtowed to the American government. The extra security doesn't apply to anyone flying a non-American airline (e.g. KLM) just Americans on American airlines flying to America. Used to be you'd have to go wander to a secondary screening station but when I flew through in 2019 they just pulled you out of line at the gate. I've not seen another airport that does this (in Europe or elsewhere).