First of all, the post is full of constructive, actionable advice. Does the advice seem good? Then that's all that matters! The post stands by itself even without knowing who patio11 is.
Personal attacks like this literally add nothing while at the same time actively stifling future discussions. You should never have a personal attack unless there is a very good, concrete reason for it to be relevant and you're still polite about it. Anything else is simply both rude and unconstructive.
Second of all, he's somebody who both has a successful business in a vaguely similar niche and used to be a successful consultant optimizing others businesses. That is, he was a professional doing exactly this sort of criticism! And people were paying him for it. Because it's extremely useful.
I legitimately have no idea what business he has talking about tarsnap this way. I clicked his "about" link and it said he made bingo card creator software.
He has a ton of HN karma, so I expected downvotes, but I'm still puzzled as to why he would make this post.
You're saying he's had success in something similar to online backups? What was it?