10/10 argument, bonus points for not addressing a single point the person made
Nano is trading on many exchanges, including Binance with volumes near Ethereum levels. They are doing just fine there. Using Bitgrail as an example for nano not working is retarded, because there is significant evidence all over the place that it is working fine.
Claiming there aren't problems in this market is stupid, is the point, and it's less safe in general. With real money, you're insured against malcious actions, but with crypto, at least for the time being, you're shit out of luck. The regulation mill is turning recently however so things might not be so bad going forward
If someone steals my cash I am also shit out of luck. Sounds like you want to use crypto through an insured bank that will take responsibility for your funds. These already exist, so your argument is flawed. Most users right now prefer to hold their own money, but this may become less popular as these banking businesses becoming more reputed.