Yes, but actually no
BIG BANG, 2PM, SHINee, U-KISS, FTISLAND, CNBLUE, Apink, Brave Girls, Block B and MYNAME who debuted as 2nd gen groups still exist and havn't disbanded yet
T-ARA never officialy disbanded and some member are still somehow together (and there is a rumored comeback, or was it even allready?)
Beast, rebranded as HIGHLIGHT still exists
SUPER JUNIOR, EPIK HIGH, SHINHWA and TVXQ who debuted as 1st gen groups still exist and havn't disbanded yet
Kangta, who debuted as 1st gen idol is still working
Luna, Amber, CL, Minzy, Park Bom, Hyoyeon, Jessica, Tiffany and Taeyeon who debuted as 2nd gen idol still work
You can't tell me that 1st and 2nd gen died yet if these people are still out there dropping music