Yeah, more or less. There are limits on how much you can get from the bank, but in general, the idea is to deposit as much as possible for interest and put the rest in the vault.
If you're only interested in getting membership, then it won't take long.
The bank limit grows with user activity, meaning that more active users can store more coins to receive higher daily interest. But if you just lurk and never participate, your limit will be lower and you'll receive fewer coins from daily interest.
Although most people are only interested in getting membership for the content+, the higher levels offer different things, such as access to exclusive threads.