Yes. I do agree with both of you... however, it would be great to be able to create a specific community around this. One of Y Combinator's advantages is that every startup they accept into their program joins their network of founders. Thus enabling founders to connect, network, share best practices, create partnerships, and help the community for the overall good for the industry.
Y Combinator is a closed network though. At least I'm not aware of them running any public forums apart from Hacker News which isn't founder specific and more of a news aggregator.
Also note that Y Combinator is not simply offering a community for founders. They are venture capitalists that fund promising startups. Their main purpose is incubating fledgling companies by injecting cold, hard, cash. The community aspect is just a side-effect and a useful one at that.
If you want to connect to crypto startup founders your best shot right now is getting in touch directly or looking out for crypto related conferences around your area.