DB is currently just cashing in on nostalgiaToriyama is specifically the one who came back to do Battle of Gods, starting everything he's doing right now, because that's what he really wanted to do. If it was cashing on nostalgia he would've come back 12 years ago to do more of the same.
The only problem with that is that he's not doing very well, but it's not nostalgia.
If I struggled to the end of my determination, to the end of my way of life with my followers, if the result is ruin, then this ruin is inevitable. Grieve. Shed tears. But you cannot regret.