I would assume that they do it because HTTPS
does complicate the pipeline on several different levels. If you want to tcpdump the https traffic, for example, you need to do SSL/TLS termination at the load balancer to get something readable. Most web servers don't make it easy to inject on the other side of the decryption; I remember having to enable some very verbose debug logs in nginx to accommodate this. Third-party tooling is necessary to take a dump of encrypted traffic and decrypt it for analysis.
It's also possible that their configuration was causing them performance problems and decreasing overhead by killing HTTPS for "unnecessary" endpoints was seen as a potential solution. Requesting a public record about a patent is not something that, at first glance, seems like it should need to be transferred over a secure protocol.
Of course, none of these are really good reasons to disable HTTPS, but they're some potential explanations.
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Separately, I think some people who remember HTTPS being used to secure "true secret" pages kind of resent the "HTTPS must be used anywhere and everywhere" trend that has taken hold. It's not that there aren't good reasons to do that, but it's also silly to pretend there aren't side effects of doing it.
From some perspectives, the need to encrypt all communication can be seen as an external concern for something like a VPN tunnel to handle. End-to-end crypto is good because it, theoretically, precludes reception from anyone who can get in the middle of the server and the VPN, but it needs to be more transparent before everyone is willing to consider that a worthwhile/important tradeoff.
One side effect of HTTPS everywhere is that the site can no longer really designate some portion of traffic as "secret". If every admin in your org needs to be able to decrypt all HTTPS traffic to debug issues, you're giving some access away. Maybe some of them would've been able to get to that data anyway, but probably many of them would not.
Again, this is not to say that that HTTPS shouldn't be used, but just some musings into why someone would not necessarily be enthusiastic about it. Working to integrate HTTPS more transparently to admins and working toward the ability to mark specific information for extra "app-layer secrecy" instead of just relying on transport-layer secrecy seem like they'd be good steps.