To be fair, although I really dislike the idea of fixed length passwords, with this many characters it's not too bad.

A full search of the password space that this outputs would take ~10^50 years at the moment, on high end hardware, and shouldn't be susceptible to attacks on patterns, assuming SHA is working properly.

One thing I would say is that with something like this you might as well just remember a really long password and tag on the name of the service at the beginning, that will give you (arguably) more security. Something like hackernewsFe26476e75256504234fC7CbBcE05aEd704b94A2.