long-term viability
It's a game. It will be up for as long as people play it.
a new person wouldn't be able to win any battles
You can't attack people who aren't logged in. Storage buildings are cheap and protect an amount of drugs from being stolen. The dev can implement a protection timer for new accounts in the future or solve the problem in other ways. He's active.
gain anything meaningful from heists
It's not an investment fund. You can play for long enough until you get something from heists if you want. You'll eventually get something, because it takes more and more resources than your production every time you want to level up your buildings further, which is good for newbies and bad for veterans. The dev is considering more options to increase game revenue (like ads) to boost the daily heist rewards a bit.