There are a lot of Berliners who love Tegel and don't want it to close even when BBI is eventually open (whenever that may be). TXL is truly a fantastic airport, and would become even better when not overcrowded.
B, C and D are as crappy as you'd expect hosting sleazyjet, ryanair, germanwings etc etc, although it's 80% business flights in the mornings and seasoned air travelers tend to make security and so on less bothersome than if you arrive at the same time as 150 hungover brits trying to get back to gatwick.. ;)
Millions of more people use Tegel than use those apartments, and if they aren’t “screwed over” living near the airport today, they wouldn’t be if it stayed open.