SHA256 will definitely be broken eventually, stopping Bitcoin mining completely.
Is this really the case? "Definitely?" If bitcoin's algo's become useless to the point of causing bitcoin to completely fail, I'm not sure people would ever have faith in cryptocurrency again. At least not the public. Hell, I wouldn't.
I read time and time again that if catastrophic flaws in SHA256 are discovered, bitcoin is the least of our problems. Not really sure if that is true or not, though.