I guess you need to read more and educate yourself, because you are not getting BTC's point if you think that not being ideal for fast micro-transactions is a flaw. Again: it was not designed with that in mind. The problems it solves are different, and deeper.
But this will stop it from being used as a currency. It will be store of value, but not currency in a sense "pay for dinner" or "buy a coffee" currency. Of course you CAN buy a dinner in few obscure places that I do not know names of in LA paying with BTC, but that's not the point.
I appreciate BTC benefits. Being decentralised is fantastic. Having a paper wallet is mind blowing. Its compressing value into a QR code. This stuff is truly, truly amazing to me. But I cringe when I hear that BTC will become a widely adopted currency.
Services can be built on top of Bitcoin that can allow you to instant off-chain transactions. And anyhow, not being able to pay your morning coffee with Bitcoin is irrelevant. 90% of the people in here agrees that there is no need to be able to pay for your chewing gum with it. You don't need it to be the "world currency" used by 5 billion people, and with a price per bitcoin of $1M. BTC covers a specific area that generates a huge demand, simply because it enables you to be more free than you were without it.
And now call it a failure...