If you could invest and earn 2% daily interests on your Bitcoins or USD without having to buy their shitcoin first and getting paid in their shitcoin then BitConnect would be a ponzi/scam. Right now they could decide to take no more loans and afford to pay everyone with their stash of millions of BitConnect coins, but when people tried to sell theese BitConnect coins the value would quickly drop to 0$ and most people would get screwd. BitConnect would still have all the Bitcoins without having scammed anyone, people just scammed themself for taking a shitty deal trading their Bitcoins for Shitcoins.
I don't see how paying out in worthless shit would make it not a scam. Otherwise every scammer could pay out in rubles or bolivars or dogecoins and avoid any responsibility.
You do not consider it worthless shit if you buy some first right? When you pay for it you give it value and the only way to earn interest on BitConnect is by buying BitConnect coins first. It is not a scam if a "scammer" sell you Rubles for your dollars/bitcoins and pay you 1% daily compounded interest on your Rubles, it just might be a bad deal for you. But offering bad deals is not against the law atleast in my country, I see bad deals everywhere I go. A majority of the people who invest in BitConnect will lose wealth, but it is for sure not a scam or would atleast make no sense for them to scam anyone when they can run with the wealth of people without scamming anyone.