I agree with Blue Ferrari, you've most likely ended up on an older 737NG which was never refitted with IFE.
Again, in regards to food, pax on CGK to SRG was never served hot food, as it's a 70 minute flight. Flights over 90 minutes would get hot meals afaik. This is the same with CGK to JOG and other Central Javan destinations as well as TKG.
Finally, I really am confused, why does Garuda only sell full flex Y these days on almost all domestic routes?? I've been looking for flights to DPS for the next few months, and they're all in excess of Rp. 3.8 mil return! For that price a couple years ago, you could've gotten 2 passengers from CGK-DPS return.