I believe blockchain is a very promising technology that we can rely on as of the moment. But we are not sure in the future because maybe in the future, someone will be able to come up with another technology that will be better that blockchain. As for now, I can say it's not a perfect solution because nothings perfect, everything has it's downside.
Yes, today, blockchain can decide many problems and some people call it the perfect decision. We do not know anything about the future - probably, the new technologies, better than this one, will appear.