Yeah, looks like 'trustify' is potentially his hosting platform and something's wrong with the certificates.

If it isn't his site and is just a complete 1:1 replica, I'm not sure what that would achieve except mess up his analytics, which could be the case. Or maybe someone's trying to inject malware into our computers through it? Hmm

I tried to go through a link he posted and through google, and they all result in the same untrusted certificate.

I would guess just don't put your billing details into his site (joking, I don't think he has anything like that on there)

Works if http instead of https. http://paulgraham.com/genius.html

It still works if https, but the website appropriately tells you that the website 'isn't secure' because there's a certificate out of date.

Using http is fine because you're just trying to access a webpage and not do any sort of transactions, but not really a good general practice to do to just make things 'work'.

Yes, but it doesn't support HTTPS (properly).