Is the encryption not good enough (and I mean in general when sites get bcrypt'd passwords stolen, etc) when owners are worried the encrypted data is in the han

Is the encryption not good enough (and I mean in general when sites get bcrypt'd passwords stolen, etc) when owners are worried the encrypted data is in the hands of intruders? As a developer I'd still be concerned if I lost such data when encrypted - so I understand - but what measures can be put in place so that as a developer/site owner you're without uncertainty that the encrypted data will never be encrypted by the attacker (eg, would take trillions of years).