It's really about who gets all that info. Why should I tell my details to a random organization? I've stayed way from many of those ICO/IEO things because I'm not too happy about my personal details revealed all over the internet.

If it's an already big and stable company and I really need to use services (Eg: Binance)I won't mind going through the KYC stuff. But seein it everywhere is not something I'm happy about.