You did great effort and it's thanks to those efforts that cryptos will really go mainstream.
A lot of times I too got to know people that were very sceptical about cryptocurrencies. BUT they accepted the idea that the Proof of Work (to make it simple, I used it as a starting point) is a form of democracy and a form to contain and prevent not agreed modifications. So they could understand that the max supply for BTC is 21M tokens, they could understand why they pay transaction fees and why some cryptos have already some aspects of Store of Value.
So when they think it's a Ponzi, remember that Bitcoin is not OneCoin/Coinspace/and many other doubtful projects that happened during the time. They were just centralized projects aimed to create rapid wealth for a restricted group of people. Bitcoin is decentralized aimed to bring wealth to everybody thanks to its key aspects of money democracy.
ponzi scheme@mikezillo ! Thanks for the remarks! I'll will not relent on the effort, with your own shared experienced, I can understand now that they are just afraid of