Having flown through Pane field recently, I can tell you there are plenty of planes rolling off the assembly line there still.
Also hot tip: Sea Tac is hot garbage, book all flights in and out of WA through Pane. It's great, what flying in the 60s must've felt like. Leather chairs and executive décor in the lobby in front of the bar between the gates. No private lounge, but you don't need one.