I don't know much about how BTC or ETH works, but why all cryptocurrencies takes so long to confirm a transaction. I think even 30s is too long, why cant it be instant like PayPal?
You are right, that time of transactions is to long. The transfer time, like preposters already stated depends on traffic in network and the fees that are paid. But to implement bitcoin to "real life" (offline shops, restaurants and so on) it is very imported to enable instant payments. Therefore a lightning network will be implemented.
of course when bitcoin is applied to offline purchases, of course, it can not be because the constantly changing bitcoin price then allows the trader to lose when the price of bitcoin becomes low, so bitcoin is as good as it is